diff --git a/src/Spout/Common/Entity/Row.php b/src/Spout/Common/Entity/Row.php
index 0cc49c73..eece8ace 100644
--- a/src/Spout/Common/Entity/Row.php
+++ b/src/Spout/Common/Entity/Row.php
@@ -18,6 +18,12 @@ class Row
      */
     protected $style;
 
+    /**
+     * Row height (default is 15)
+     * @var string
+     */
+    protected $height = '15';
+
     /**
      * Row constructor.
      * @param Cell[] $cells
@@ -126,4 +132,25 @@ public function toArray()
             return $cell->getValue();
         }, $this->cells);
     }
+
+    /**
+     * Set row height
+     * @param string $height
+     * @return Row
+     */
+    public function setHeight($height)
+    {
+        $this->height = $height;
+
+        return $this;
+    }
+
+    /**
+     * Returns row height
+     * @return string
+     */
+    public function getHeight()
+    {
+        return $this->height;
+    }
 }
diff --git a/src/Spout/Common/Entity/Style/Style.php b/src/Spout/Common/Entity/Style/Style.php
index 7e989a46..97688e92 100644
--- a/src/Spout/Common/Entity/Style/Style.php
+++ b/src/Spout/Common/Entity/Style/Style.php
@@ -66,6 +66,11 @@ class Style
     /** @var bool Whether the wrap text property was set */
     private $hasSetWrapText = false;
 
+    /** @var bool Whether the cell should shrink to fit to content */
+    private $shouldShrinkToFit = false;
+    /** @var bool Whether the shouldShrinkToFit text property was set */
+    private $hasSetShrinkToFit = false;
+
     /** @var Border */
     private $border;
 
@@ -463,4 +468,33 @@ public function shouldApplyFormat()
     {
         return $this->hasSetFormat;
     }
+
+    /**
+     * Sets should shrink to fit
+     * @param bool $shrinkToFit
+     * @return Style
+     */
+    public function setShouldShrinkToFit($shrinkToFit = true)
+    {
+        $this->hasSetShrinkToFit = true;
+        $this->shouldShrinkToFit = $shrinkToFit;
+
+        return $this;
+    }
+
+    /**
+     * @return bool Whether format should be applied
+     */
+    public function shouldShrinkToFit()
+    {
+        return $this->shouldShrinkToFit;
+    }
+
+    /**
+     * @return bool
+     */
+    public function hasSetShrinkToFit()
+    {
+        return $this->hasSetShrinkToFit;
+    }
 }
diff --git a/src/Spout/Common/Manager/OptionsManagerAbstract.php b/src/Spout/Common/Manager/OptionsManagerAbstract.php
index 5670b95b..2381c52d 100644
--- a/src/Spout/Common/Manager/OptionsManagerAbstract.php
+++ b/src/Spout/Common/Manager/OptionsManagerAbstract.php
@@ -51,6 +51,23 @@ public function setOption($optionName, $optionValue)
         }
     }
 
+    /**
+     * Add an option to the internal list of options
+     * Used only for mergeCells() for now
+     * @param mixed $optionName
+     * @param mixed $optionValue
+     * @return void
+     */
+    public function addOption($optionName, $optionValue)
+    {
+        if (\in_array($optionName, $this->supportedOptions)) {
+            if (!isset($this->options[$optionName])) {
+                $this->options[$optionName] = [];
+            }
+            $this->options[$optionName][] = $optionValue;
+        }
+    }
+
     /**
      * @param string $optionName
      * @return mixed|null The set option or NULL if no option with given name found
diff --git a/src/Spout/Common/Manager/OptionsManagerInterface.php b/src/Spout/Common/Manager/OptionsManagerInterface.php
index 21fea0c5..bccb1c39 100644
--- a/src/Spout/Common/Manager/OptionsManagerInterface.php
+++ b/src/Spout/Common/Manager/OptionsManagerInterface.php
@@ -19,4 +19,13 @@ public function setOption($optionName, $optionValue);
      * @return mixed|null The set option or NULL if no option with given name found
      */
     public function getOption($optionName);
+
+    /**
+     * Add an option to the internal list of options
+     * Used only for mergeCells() for now
+     * @param mixed $optionName
+     * @param mixed $optionValue
+     * @return void
+     */
+    public function addOption($optionName, $optionValue);
 }
diff --git a/src/Spout/Reader/ODS/SheetIterator.php b/src/Spout/Reader/ODS/SheetIterator.php
index f35b8523..c7b8cd9d 100644
--- a/src/Spout/Reader/ODS/SheetIterator.php
+++ b/src/Spout/Reader/ODS/SheetIterator.php
@@ -28,13 +28,13 @@ class SheetIterator implements IteratorInterface
     const XML_ATTRIBUTE_TABLE_STYLE_NAME = 'table:style-name';
     const XML_ATTRIBUTE_TABLE_DISPLAY = 'table:display';
 
-    /** @var string $filePath Path of the file to be read */
+    /** @var string Path of the file to be read */
     protected $filePath;
 
     /** @var \Box\Spout\Common\Manager\OptionsManagerInterface Reader's options manager */
     protected $optionsManager;
 
-    /** @var InternalEntityFactory $entityFactory Factory to create entities */
+    /** @var InternalEntityFactory Factory to create entities */
     protected $entityFactory;
 
     /** @var XMLReader The XMLReader object that will help read sheet's XML data */
diff --git a/src/Spout/Reader/XLSX/Manager/SharedStringsManager.php b/src/Spout/Reader/XLSX/Manager/SharedStringsManager.php
index caaeed76..8850a69b 100644
--- a/src/Spout/Reader/XLSX/Manager/SharedStringsManager.php
+++ b/src/Spout/Reader/XLSX/Manager/SharedStringsManager.php
@@ -43,7 +43,7 @@ class SharedStringsManager
     /** @var InternalEntityFactory Factory to create entities */
     protected $entityFactory;
 
-    /** @var HelperFactory $helperFactory Factory to create helpers */
+    /** @var HelperFactory Factory to create helpers */
     protected $helperFactory;
 
     /** @var CachingStrategyFactory Factory to create shared strings caching strategies */
diff --git a/src/Spout/Reader/XLSX/RowIterator.php b/src/Spout/Reader/XLSX/RowIterator.php
index 4af4530d..a54b8b19 100644
--- a/src/Spout/Reader/XLSX/RowIterator.php
+++ b/src/Spout/Reader/XLSX/RowIterator.php
@@ -35,7 +35,7 @@ class RowIterator implements IteratorInterface
     /** @var string Path of the XLSX file being read */
     protected $filePath;
 
-    /** @var string $sheetDataXMLFilePath Path of the sheet data XML file as in [Content_Types].xml */
+    /** @var string Path of the sheet data XML file as in [Content_Types].xml */
     protected $sheetDataXMLFilePath;
 
     /** @var \Box\Spout\Reader\Wrapper\XMLReader The XMLReader object that will help read sheet's XML data */
diff --git a/src/Spout/Writer/Common/Creator/Style/StyleBuilder.php b/src/Spout/Writer/Common/Creator/Style/StyleBuilder.php
index bc2d406f..72fdcf0c 100644
--- a/src/Spout/Writer/Common/Creator/Style/StyleBuilder.php
+++ b/src/Spout/Writer/Common/Creator/Style/StyleBuilder.php
@@ -183,6 +183,19 @@ public function setFormat($format)
         return $this;
     }
 
+    /**
+     * Set should shrink to fit
+     * @param bool $shrinkToFit
+     * @return StyleBuilder
+     * @api
+     */
+    public function setShouldShrinkToFit($shrinkToFit = true)
+    {
+        $this->style->setShouldShrinkToFit($shrinkToFit);
+
+        return $this;
+    }
+
     /**
      * Returns the configured style. The style is cached and can be reused.
      *
diff --git a/src/Spout/Writer/Common/Entity/Options.php b/src/Spout/Writer/Common/Entity/Options.php
index d7152bb6..0baa6282 100644
--- a/src/Spout/Writer/Common/Entity/Options.php
+++ b/src/Spout/Writer/Common/Entity/Options.php
@@ -20,4 +20,10 @@ abstract class Options
 
     // XLSX specific options
     const SHOULD_USE_INLINE_STRINGS = 'shouldUseInlineStrings';
+
+    // XLSX column widths
+    const COLUMN_WIDTHS = 'columnWidths';
+
+    // XLSX merge cells
+    const MERGE_CELLS = 'mergeCells';
 }
diff --git a/src/Spout/Writer/Common/Entity/Sheet.php b/src/Spout/Writer/Common/Entity/Sheet.php
index aabdd91f..63915716 100644
--- a/src/Spout/Writer/Common/Entity/Sheet.php
+++ b/src/Spout/Writer/Common/Entity/Sheet.php
@@ -27,6 +27,9 @@ class Sheet
     /** @var SheetManager Sheet manager */
     private $sheetManager;
 
+    /** @var bool Sheet is started */
+    private $isSheetStarted = false;
+
     /**
      * @param int $sheetIndex Index of the sheet, based on order in the workbook (zero-based)
      * @param string $associatedWorkbookId ID of the sheet's associated workbook
@@ -108,4 +111,23 @@ public function setIsVisible($isVisible)
 
         return $this;
     }
+
+    /**
+     * @return bool isSheetStarted Sheet was started
+     */
+    public function isSheetStarted()
+    {
+        return $this->isSheetStarted;
+    }
+
+    /**
+     * @param bool $isSheetStarted Set if sheet was started
+     * @return Sheet
+     */
+    public function setIsSheetStarted($isSheetStarted)
+    {
+        $this->isSheetStarted = $isSheetStarted;
+
+        return $this;
+    }
 }
diff --git a/src/Spout/Writer/Common/Manager/Style/StyleMerger.php b/src/Spout/Writer/Common/Manager/Style/StyleMerger.php
index 806c8d55..1adeb185 100644
--- a/src/Spout/Writer/Common/Manager/Style/StyleMerger.php
+++ b/src/Spout/Writer/Common/Manager/Style/StyleMerger.php
@@ -85,6 +85,9 @@ private function mergeCellProperties(Style $styleToUpdate, Style $style, Style $
         if (!$style->hasSetWrapText() && $baseStyle->shouldWrapText()) {
             $styleToUpdate->setShouldWrapText();
         }
+        if (!$style->hasSetShrinkToFit() && $baseStyle->shouldShrinkToFit()) {
+            $styleToUpdate->setShouldShrinkToFit();
+        }
         if (!$style->hasSetCellAlignment() && $baseStyle->shouldApplyCellAlignment()) {
             $styleToUpdate->setCellAlignment($baseStyle->getCellAlignment());
         }
diff --git a/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php b/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php
index b5135555..653778c7 100644
--- a/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php
+++ b/src/Spout/Writer/Common/Manager/WorkbookManagerAbstract.php
@@ -44,7 +44,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
     /** @var InternalEntityFactory Factory to create entities */
     protected $entityFactory;
 
-    /** @var ManagerFactoryInterface $managerFactory Factory to create managers */
+    /** @var ManagerFactoryInterface Factory to create managers */
     protected $managerFactory;
 
     /** @var Worksheet The worksheet where data will be written to */
diff --git a/src/Spout/Writer/ODS/Creator/ManagerFactory.php b/src/Spout/Writer/ODS/Creator/ManagerFactory.php
index f38c5000..a5b77ee4 100644
--- a/src/Spout/Writer/ODS/Creator/ManagerFactory.php
+++ b/src/Spout/Writer/ODS/Creator/ManagerFactory.php
@@ -22,7 +22,7 @@ class ManagerFactory implements ManagerFactoryInterface
     /** @var InternalEntityFactory */
     protected $entityFactory;
 
-    /** @var HelperFactory $helperFactory */
+    /** @var HelperFactory */
     protected $helperFactory;
 
     /**
diff --git a/src/Spout/Writer/WriterAbstract.php b/src/Spout/Writer/WriterAbstract.php
index d96a6280..bbaa735a 100644
--- a/src/Spout/Writer/WriterAbstract.php
+++ b/src/Spout/Writer/WriterAbstract.php
@@ -33,7 +33,7 @@ abstract class WriterAbstract implements WriterInterface
     /** @var GlobalFunctionsHelper Helper to work with global functions */
     protected $globalFunctionsHelper;
 
-    /** @var HelperFactory $helperFactory */
+    /** @var HelperFactory */
     protected $helperFactory;
 
     /** @var OptionsManagerInterface Writer options manager */
diff --git a/src/Spout/Writer/WriterMultiSheetsAbstract.php b/src/Spout/Writer/WriterMultiSheetsAbstract.php
index 8170b679..58f22b82 100644
--- a/src/Spout/Writer/WriterMultiSheetsAbstract.php
+++ b/src/Spout/Writer/WriterMultiSheetsAbstract.php
@@ -4,6 +4,7 @@
 
 use Box\Spout\Common\Creator\HelperFactory;
 use Box\Spout\Common\Entity\Row;
+use Box\Spout\Common\Exception\IOException;
 use Box\Spout\Common\Helper\GlobalFunctionsHelper;
 use Box\Spout\Common\Manager\OptionsManagerInterface;
 use Box\Spout\Writer\Common\Creator\ManagerFactoryInterface;
@@ -97,6 +98,7 @@ public function getSheets()
      * Creates a new sheet and make it the current sheet. The data will now be written to this sheet.
      *
      * @throws WriterNotOpenedException If the writer has not been opened yet
+     * @throws IOException If unable to open the sheet for writing
      * @return Sheet The created sheet
      */
     public function addNewSheetAndMakeItCurrent()
diff --git a/src/Spout/Writer/XLSX/Creator/ManagerFactory.php b/src/Spout/Writer/XLSX/Creator/ManagerFactory.php
index f27a2f2f..aa3bcd5c 100644
--- a/src/Spout/Writer/XLSX/Creator/ManagerFactory.php
+++ b/src/Spout/Writer/XLSX/Creator/ManagerFactory.php
@@ -24,7 +24,7 @@ class ManagerFactory implements ManagerFactoryInterface
     /** @var InternalEntityFactory */
     protected $entityFactory;
 
-    /** @var HelperFactory $helperFactory */
+    /** @var HelperFactory */
     protected $helperFactory;
 
     /**
diff --git a/src/Spout/Writer/XLSX/Manager/OptionsManager.php b/src/Spout/Writer/XLSX/Manager/OptionsManager.php
index d3b5cd42..40e299ef 100644
--- a/src/Spout/Writer/XLSX/Manager/OptionsManager.php
+++ b/src/Spout/Writer/XLSX/Manager/OptionsManager.php
@@ -39,6 +39,8 @@ protected function getSupportedOptions()
             Options::DEFAULT_ROW_STYLE,
             Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY,
             Options::SHOULD_USE_INLINE_STRINGS,
+            Options::COLUMN_WIDTHS,
+            Options::MERGE_CELLS,
         ];
     }
 
@@ -56,5 +58,7 @@ protected function setDefaultOptions()
         $this->setOption(Options::DEFAULT_ROW_STYLE, $defaultRowStyle);
         $this->setOption(Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY, true);
         $this->setOption(Options::SHOULD_USE_INLINE_STRINGS, true);
+        $this->setOption(Options::COLUMN_WIDTHS, []);
+        $this->setOption(Options::MERGE_CELLS, []);
     }
 }
diff --git a/src/Spout/Writer/XLSX/Manager/Style/StyleManager.php b/src/Spout/Writer/XLSX/Manager/Style/StyleManager.php
index f0ca9d9e..437b4332 100644
--- a/src/Spout/Writer/XLSX/Manager/Style/StyleManager.php
+++ b/src/Spout/Writer/XLSX/Manager/Style/StyleManager.php
@@ -249,7 +249,7 @@ protected function getCellXfsSectionContent()
 
             $content .= \sprintf(' applyBorder="%d"', $style->shouldApplyBorder() ? 1 : 0);
 
-            if ($style->shouldApplyCellAlignment() || $style->shouldWrapText()) {
+            if ($style->shouldApplyCellAlignment() || $style->shouldWrapText() || $style->shouldShrinkToFit()) {
                 $content .= ' applyAlignment="1">';
                 $content .= '<alignment';
                 if ($style->shouldApplyCellAlignment()) {
@@ -258,6 +258,10 @@ protected function getCellXfsSectionContent()
                 if ($style->shouldWrapText()) {
                     $content .= ' wrapText="1"';
                 }
+                if ($style->shouldShrinkToFit()) {
+                    $content .= ' shrinkToFit="true"';
+                }
+
                 $content .= '/>';
                 $content .= '</xf>';
             } else {
diff --git a/src/Spout/Writer/XLSX/Manager/WorksheetManager.php b/src/Spout/Writer/XLSX/Manager/WorksheetManager.php
index 741d0aa8..4a716035 100644
--- a/src/Spout/Writer/XLSX/Manager/WorksheetManager.php
+++ b/src/Spout/Writer/XLSX/Manager/WorksheetManager.php
@@ -37,6 +37,8 @@ class WorksheetManager implements WorksheetManagerInterface
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">
 EOD;
+    /** @var OptionsManagerInterface */
+    private $optionsManager;
 
     /** @var bool Whether inline or shared strings should be used */
     protected $shouldUseInlineStrings;
@@ -84,6 +86,7 @@ public function __construct(
         StringHelper $stringHelper,
         InternalEntityFactory $entityFactory
     ) {
+        $this->optionsManager = $optionsManager;
         $this->shouldUseInlineStrings = $optionsManager->getOption(Options::SHOULD_USE_INLINE_STRINGS);
         $this->rowManager = $rowManager;
         $this->styleManager = $styleManager;
@@ -113,7 +116,6 @@ public function startSheet(Worksheet $worksheet)
         $worksheet->setFilePointer($sheetFilePointer);
 
         \fwrite($sheetFilePointer, self::SHEET_XML_FILE_HEADER);
-        \fwrite($sheetFilePointer, '<sheetData>');
     }
 
     /**
@@ -153,11 +155,28 @@ public function addRow(Worksheet $worksheet, Row $row)
      */
     private function addNonEmptyRow(Worksheet $worksheet, Row $row)
     {
+        if (!$worksheet->getExternalSheet()->isSheetStarted()) {
+            // create nodes for columns widths
+            if ($this->optionsManager->getOption(Options::COLUMN_WIDTHS)) {
+                $colsString = '<cols>';
+                foreach ($this->optionsManager->getOption(Options::COLUMN_WIDTHS) as $index => $width) {
+                    $index++;
+                    $colsString.= '<col collapsed="false" customWidth="true" hidden="false" outlineLevel="0" style="0" max="' . $index . '" min="' . $index . '"  width="' . $width . '"/>';
+                }
+                $colsString.='</cols>';
+                \fwrite($worksheet->getFilePointer(), $colsString);
+            }
+
+            \fwrite($worksheet->getFilePointer(), '<sheetData>');
+            $worksheet->getExternalSheet()->setIsSheetStarted(true);
+        }
+
         $rowStyle = $row->getStyle();
         $rowIndexOneBased = $worksheet->getLastWrittenRowIndex() + 1;
         $numCells = $row->getNumCells();
+        $rowHeight = $row->getHeight();
 
-        $rowXML = '<row r="' . $rowIndexOneBased . '" spans="1:' . $numCells . '">';
+        $rowXML = '<row r="' . $rowIndexOneBased . '" spans="1:' . $numCells . '" customHeight="true"' . ' ht="' . $rowHeight . '">';
 
         foreach ($row->getCells() as $columnIndexZeroBased => $cell) {
             $rowXML .= $this->applyStyleAndGetCellXML($cell, $rowStyle, $rowIndexOneBased, $columnIndexZeroBased);
@@ -270,7 +289,26 @@ public function close(Worksheet $worksheet)
             return;
         }
 
+        if (!$worksheet->getExternalSheet()->isSheetStarted()) {
+            \fwrite($worksheetFilePointer, '<sheetData>');
+            $worksheet->getExternalSheet()->setIsSheetStarted(true);
+        }
+
         \fwrite($worksheetFilePointer, '</sheetData>');
+
+        // create nodes for merge cells
+        if ($this->optionsManager->getOption(Options::MERGE_CELLS)) {
+            $mergeCellString = '<mergeCells count="' . \count($this->optionsManager->getOption(Options::MERGE_CELLS)) . '">';
+            foreach ($this->optionsManager->getOption(Options::MERGE_CELLS) as $values) {
+                $output = \array_map(function ($value) {
+                    return CellHelper::getColumnLettersFromColumnIndex($value[0]) . $value[1];
+                }, $values);
+                $mergeCellString.= '<mergeCell ref="' . \implode(':', $output) . '"/>';
+            }
+            $mergeCellString.= '</mergeCells>';
+            \fwrite($worksheet->getFilePointer(), $mergeCellString);
+        }
+
         \fwrite($worksheetFilePointer, '</worksheet>');
         \fclose($worksheetFilePointer);
     }
diff --git a/src/Spout/Writer/XLSX/Writer.php b/src/Spout/Writer/XLSX/Writer.php
index 9d928fc9..41eb03a3 100644
--- a/src/Spout/Writer/XLSX/Writer.php
+++ b/src/Spout/Writer/XLSX/Writer.php
@@ -47,4 +47,34 @@ public function setShouldUseInlineStrings($shouldUseInlineStrings)
 
         return $this;
     }
+
+    /**
+     * Set columns widths as list. If value is null will set column with default width (8.43)
+     * @param array $columnWidths
+     * @return WriterMultiSheetsAbstract
+     */
+    public function setColumnWidths(array $columnWidths)
+    {
+        $this->optionsManager->setOption(Options::COLUMN_WIDTHS, $columnWidths);
+
+        return $this;
+    }
+
+    /**
+     * Merge cells.
+     * Row coordinates are indexed from 1, columns from 0 (A = 0),
+     * so a merge B2:G2 looks like $writer->mergeCells([1,2], [6, 2]);
+     *
+     * You may use CellHelper::getColumnLettersFromColumnIndex() to convert from "B2" to "[1,2]"
+     *
+     * @param int[] $range1 - top left cell's coordinate [column, row]
+     * @param int[] $range2 - bottom right cell's coordinate [column, row]
+     * @return $this
+     */
+    public function mergeCells(array $range1, array $range2)
+    {
+        $this->optionsManager->addOption(Options::MERGE_CELLS, [$range1, $range2]);
+
+        return $this;
+    }
 }
diff --git a/tests/Spout/Common/Manager/OptionsManagerTest.php b/tests/Spout/Common/Manager/OptionsManagerTest.php
index e2f0c5cc..66da195a 100644
--- a/tests/Spout/Common/Manager/OptionsManagerTest.php
+++ b/tests/Spout/Common/Manager/OptionsManagerTest.php
@@ -73,4 +73,28 @@ public function testOptionsManagerShouldReturnNullIfNoOptionNotSupported()
         $optionsManager->setOption('not-supported', 'something');
         $this->assertNull($optionsManager->getOption('not-supported'));
     }
+
+    /**
+     * @return void
+     */
+    public function testOptionManagerShouldReturnArrayIfListOptionsAdded()
+    {
+        $optionsManager = $this->optionsManager;
+        $optionsManager->addOption('bar', 'something');
+        $optionsManager->addOption('bar', 'something-else');
+        $this->assertIsArray($optionsManager->getOption('bar'));
+        $this->assertCount(2, $optionsManager->getOption('bar'));
+        $this->assertEquals('something', $optionsManager->getOption('bar')[0]);
+        $this->assertEquals('something-else', $optionsManager->getOption('bar')[1]);
+    }
+
+    /**
+     * @return void
+     */
+    public function testOptionsManagerShouldReturnNullIfListOptionNotSupported()
+    {
+        $optionsManager = $this->optionsManager;
+        $optionsManager->addOption('not-supported', 'something');
+        $this->assertNull($optionsManager->getOption('not-supported'));
+    }
 }
diff --git a/tests/Spout/Reader/CSV/SpoutTestStream.php b/tests/Spout/Reader/CSV/SpoutTestStream.php
index 3bfd06e1..d66e8117 100644
--- a/tests/Spout/Reader/CSV/SpoutTestStream.php
+++ b/tests/Spout/Reader/CSV/SpoutTestStream.php
@@ -14,10 +14,10 @@ class SpoutTestStream
     const PATH_TO_CSV_RESOURCES = 'tests/resources/csv/';
     const CSV_EXTENSION = '.csv';
 
-    /** @var int $position */
+    /** @var int */
     private $position;
 
-    /** @var resource $fileHandle */
+    /** @var resource */
     private $fileHandle;
 
     /**
diff --git a/tests/Spout/Writer/XLSX/WriterTest.php b/tests/Spout/Writer/XLSX/WriterTest.php
index 15cc4e46..16b852cf 100644
--- a/tests/Spout/Writer/XLSX/WriterTest.php
+++ b/tests/Spout/Writer/XLSX/WriterTest.php
@@ -7,6 +7,7 @@
 use Box\Spout\Common\Exception\InvalidArgumentException;
 use Box\Spout\Common\Exception\IOException;
 use Box\Spout\Common\Exception\SpoutException;
+use Box\Spout\Reader\Wrapper\XMLReader;
 use Box\Spout\TestUsingResource;
 use Box\Spout\Writer\Common\Creator\WriterEntityFactory;
 use Box\Spout\Writer\Exception\WriterAlreadyOpenedException;
@@ -527,6 +528,105 @@ public function testAddRowShouldEscapeControlCharacters()
         $this->assertInlineDataWasWrittenToSheet($fileName, 1, 'control _x0015_ character');
     }
 
+    /**
+     * @return void
+     */
+    public function testAddRowShouldSupportRowHeights()
+    {
+        $fileName = 'test_add_row_should_support_row_heights.xlsx';
+        $dataRows = $this->createRowsFromValues([
+            ['First row with default height'],
+            ['Second row with custom height'],
+        ]);
+
+        $dataRows[1]->setHeight('23');
+
+        $this->writeToXLSXFile($dataRows, $fileName);
+        $firstRow = $this->getXmlRowFromXmlFile($fileName, 1, 1);
+        $secondRow = $this->getXmlRowFromXmlFile($fileName, 1, 2);
+        $this->assertEquals('15', $firstRow->getAttribute('ht'), '1st row does not have default height.');
+        $this->assertEquals('23', $secondRow->getAttribute('ht'), '2nd row does not have custom height.');
+    }
+
+    /**
+     * @return void
+     */
+    public function testAddRowShouldSupportColumnWidths()
+    {
+        $fileName = 'test_add_row_should_support_column_widths.xlsx';
+        $this->createGeneratedFolderIfNeeded($fileName);
+        $resourcePath = $this->getGeneratedResourcePath($fileName);
+        $writer = WriterEntityFactory::createXLSXWriter();
+        $writer->setShouldUseInlineStrings(true);
+        $writer->openToFile($resourcePath);
+
+        $columnWidths = [1, 2, 3, 4];
+        $writer->setColumnWidths($columnWidths);
+        $writer->addRows($this->createRowsFromValues([
+            ['Test cell'],
+        ]));
+        $writer->close();
+
+        $xmlReader = $this->getXmlReaderForSheetFromXmlFile($fileName, 1);
+        $xmlReader->readUntilNodeFound('cols');
+        $this->assertEquals('cols', $xmlReader->getCurrentNodeName(), 'Sheet does not have cols tag');
+        $this->assertEquals(count($columnWidths), $xmlReader->expand()->childNodes->length, 'Sheet does not have the specified number of column definitions');
+        foreach ($columnWidths as $index => $columnWidth) {
+            $xmlReader->readUntilNodeFound('col');
+            $this->assertEquals($index + 1, $xmlReader->expand()->getAttribute('min'));
+            $this->assertEquals($index + 1, $xmlReader->expand()->getAttribute('max'));
+            $this->assertEquals($columnWidth, $xmlReader->expand()->getAttribute('width'));
+        }
+    }
+
+    /**
+     * @return void
+     */
+    public function testCloseShouldAddMergeCellTags()
+    {
+        $fileName = 'test_add_row_should_support_column_widths.xlsx';
+        $this->createGeneratedFolderIfNeeded($fileName);
+        $resourcePath = $this->getGeneratedResourcePath($fileName);
+        $writer = WriterEntityFactory::createXLSXWriter();
+        $writer->setShouldUseInlineStrings(true);
+        $writer->openToFile($resourcePath);
+
+        $writer->mergeCells([0, 1], [3, 1]);
+        $writer->mergeCells([2, 3], [10, 3]);
+        $writer->close();
+
+        $xmlReader = $this->getXmlReaderForSheetFromXmlFile($fileName, 1);
+        $xmlReader->readUntilNodeFound('mergeCells');
+        $this->assertEquals('mergeCells', $xmlReader->getCurrentNodeName(), 'Sheet does not have mergeCells tag');
+        $this->assertEquals(2, $xmlReader->expand()->childNodes->length, 'Sheet does not have the specified number of mergeCell definitions');
+        $xmlReader->readUntilNodeFound('mergeCell');
+        $this->assertEquals('A1:D1', $xmlReader->expand()->getAttribute('ref'), 'Merge ref for first range is not valid.');
+        $xmlReader->readUntilNodeFound('mergeCell');
+        $this->assertEquals('C3:K3', $xmlReader->expand()->getAttribute('ref'), 'Merge ref for second range is not valid.');
+    }
+
+    /**
+     * @return void
+     */
+    public function testGeneratedFileShouldBeValidForEmptySheets()
+    {
+        $fileName = 'test_empty_sheet.xlsx';
+        $this->createGeneratedFolderIfNeeded($fileName);
+        $resourcePath = $this->getGeneratedResourcePath($fileName);
+        $writer = WriterEntityFactory::createXLSXWriter();
+        $writer->openToFile($resourcePath);
+
+        $writer->addNewSheetAndMakeItCurrent();
+        $writer->close();
+
+        $xmlReader = $this->getXmlReaderForSheetFromXmlFile($fileName, 1);
+        $xmlReader->setParserProperty(XMLReader::VALIDATE, true);
+        $this->assertTrue($xmlReader->isValid(), 'worksheet xml is not valid');
+        $xmlReader->setParserProperty(XMLReader::VALIDATE, false);
+        $xmlReader->readUntilNodeFound('sheetData');
+        $this->assertEquals('sheetData', $xmlReader->getCurrentNodeName(), 'worksheet xml does not have sheetData');
+    }
+
     /**
      * @return void
      */
@@ -641,4 +741,42 @@ private function assertSharedStringWasWritten($fileName, $sharedString, $message
 
         $this->assertContains($sharedString, $xmlContents, $message);
     }
+
+    /**
+     * @param $fileName
+     * @param $sheetIndex - 1 based
+     * @return XMLReader
+     */
+    private function getXmlReaderForSheetFromXmlFile($fileName, $sheetIndex)
+    {
+        $resourcePath = $this->getGeneratedResourcePath($fileName);
+
+        $xmlReader = new XMLReader();
+        $xmlReader->openFileInZip($resourcePath, 'xl/worksheets/sheet' . $sheetIndex . '.xml');
+
+        return $xmlReader;
+    }
+
+    /**
+     * @param $fileName
+     * @param $sheetIndex - 1 based
+     * @param $rowIndex - 1 based
+     * @throws \Box\Spout\Reader\Exception\XMLProcessingException
+     * @return \DOMNode|null
+     */
+    private function getXmlRowFromXmlFile($fileName, $sheetIndex, $rowIndex)
+    {
+        $xmlReader = $this->getXmlReaderForSheetFromXmlFile($fileName, $sheetIndex);
+        $xmlReader->readUntilNodeFound('sheetData');
+
+        for ($i = 0; $i < $rowIndex; $i++) {
+            $xmlReader->readUntilNodeFound('row');
+        }
+
+        $row = $xmlReader->expand();
+
+        $xmlReader->close();
+
+        return $row;
+    }
 }
diff --git a/tests/Spout/Writer/XLSX/WriterWithStyleTest.php b/tests/Spout/Writer/XLSX/WriterWithStyleTest.php
index da0aec29..3baa6657 100644
--- a/tests/Spout/Writer/XLSX/WriterWithStyleTest.php
+++ b/tests/Spout/Writer/XLSX/WriterWithStyleTest.php
@@ -306,6 +306,24 @@ public function testAddRowShouldApplyCellAlignment()
         $this->assertFirstChildHasAttributeEquals(CellAlignment::RIGHT, $xfElement, 'alignment', 'horizontal');
     }
 
+    /**
+     * @return void
+     */
+    public function testAddRowShouldApplyShrinkToFit()
+    {
+        $fileName = 'test_add_row_should_apply_shrink_to_fit.xlsx';
+
+        $shrinkToFitStyle = (new StyleBuilder())->setShouldShrinkToFit()->build();
+        $dataRows = $this->createStyledRowsFromValues([['xlsx--11']], $shrinkToFitStyle);
+
+        $this->writeToXLSXFile($dataRows, $fileName);
+
+        $cellXfsDomElement = $this->getXmlSectionFromStylesXmlFile($fileName, 'cellXfs');
+        $xfElement = $cellXfsDomElement->getElementsByTagName('xf')->item(1);
+        $this->assertEquals(1, $xfElement->getAttribute('applyAlignment'));
+        $this->assertFirstChildHasAttributeEquals('true', $xfElement, 'alignment', 'shrinkToFit');
+    }
+
     /**
      * @return void
      */