diff --git a/DESCRIPTION b/DESCRIPTION
index 46b9aa4..652c777 100755
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,8 +1,10 @@
 Package: textgRid
 Title: Praat TextGrid Objects in R
 Version: 1.0.1.9000
-Authors@R: person("Patrick", "Reidy", email = "patrick.francis.reidy@gmail.com", 
-    role = c("aut", "cre"))
+Authors@R: c(
+    person("Patrick", "Reidy", email = "patrick.francis.reidy@gmail.com", 
+    role = c("aut", "cre")),
+    person("Tobias", "Busch", email = "teebusch@gmail.com", role = "ctb"))
 Description: The software application Praat can be used to annotate
     waveform data (e.g., to mark intervals of interest or to label events).
     (See <http://www.fon.hum.uva.nl/praat/> for more information about Praat.)
@@ -21,8 +23,8 @@ Suggests:
 License: GPL-3
 Encoding: UTF-8
 LazyData: true
-RoxygenNote: 5.0.1
-Collate:
+RoxygenNote: 6.0.1
+Collate: 
     'Tier-class.R'
     'IntervalTier-class.R'
     'IntervalTier-accessors.R'
@@ -42,5 +44,6 @@ Collate:
     'finders.R'
     'length.R'
     'textgRid.R'
+    'writeTextGrid.R'
 URL: www.praat.org, http://www.fon.hum.uva.nl/praat/manual/TextGrid.html
 BugReports: https://github.com/patrickreidy/textgRid
diff --git a/NAMESPACE b/NAMESPACE
index e43200a..0119210 100755
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -17,6 +17,7 @@ export(textGridEndTime)
 export(textGridStartTime)
 export(tierName)
 export(tierNumber)
+export(writeTextGrid)
 exportClasses(IntervalTier)
 exportClasses(PointTier)
 exportClasses(TextGrid)
diff --git a/NEWS.md b/NEWS.md
index 9e896ef..1953751 100755
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,7 +1,11 @@
-# v1.0.1.9000
+# v1.0.1.9001
 
 **_Current development version on Github_**
 
+* `writeTextGrid` function for `TextGrid`s.
+
+# v1.0.1.9000
+
 * `length` methods for `IntervalTier`s and `PointTier`s.
 * `Tier@number` slot changed from `numeric` to `integer`.
 * `as.data.frame` methods for `IntervalTier`s, `PointTier`s, and `TextGrid`s.
diff --git a/R/IntervalTier-constructor.R b/R/IntervalTier-constructor.R
index be8a86d..47bf5f3 100755
--- a/R/IntervalTier-constructor.R
+++ b/R/IntervalTier-constructor.R
@@ -18,7 +18,7 @@ NULL
 #' @importFrom methods setGeneric
 setGeneric(
   name = 'IntervalTier',
-  def  = function(praatText, ...) {
+  def  = function(x, ...) {
     standardGeneric('IntervalTier')
   }
 )
@@ -27,15 +27,56 @@ setGeneric(
 #' @importFrom methods setMethod new
 setMethod(
   f   = 'IntervalTier',
-  sig = c(praatText = 'character'),
-  def = function(praatText) {
+  sig = c(x = 'character'),
+  def = function(x) {
     # Initialize the IntervalTier object.
     new(Class = 'IntervalTier',
-        name       = .TierName(praatText),
-        number     = .TierNumber(praatText),
-        startTimes = .IntervalStartTimes(praatText),
-        endTimes   = .IntervalEndTimes(praatText),
-        labels     = .IntervalLabels(praatText)
+        name       = .TierName(x),
+        number     = .TierNumber(x),
+        startTimes = .IntervalStartTimes(x),
+        endTimes   = .IntervalEndTimes(x),
+        labels     = .IntervalLabels(x)
+    )
+  }
+)
+
+
+#' @rdname IntervalTier-constructor
+#' @importFrom methods setMethod new
+setMethod(
+  f   = 'IntervalTier',
+  sig = c(x = 'data.frame'),
+  def = function(x, startTime = 0, endTime = NULL) {
+    # TODO: Check if TierName column exists exists
+    .name <- x$TierName[1]
+    # TODO: Check if TierNumber col exists
+    .number <- x$TierNumber[1]
+    # TODO: Check if StartTime col exists
+    # TODO: Check if EndTime col exists
+    endTime = max(endTime, max(x$EndTime))
+    # TODO: Check if Label col exists
+    x <- x[, c('StartTime', 'EndTime', 'Label')]
+    x <- x[order(x$StartTime), ]
+    .endPrevious <- c(startTime, x$EndTime)
+    .startCurrent <- c(x$StartTime, endTime)
+    .gap <- .startCurrent - .endPrevious
+    # TODO: Check whether annotations are non-overlapping, with any(.gap < 0)
+    # Fill Gaps in Annotations
+    .gaps <- data.frame(
+      StartTime = .endPrevious,
+      EndTime = .startCurrent,
+      Label = NA
+    )
+    .gaps <- .gaps[.gap > 0, ]
+    x <- rbind(x, .gaps)
+    x <- x[order(x$StartTime), ]
+    # Initialize the IntervalTier object.
+    new(Class = 'IntervalTier',
+        name       = .name,
+        number     = .number,
+        startTimes = x$StartTime,
+        endTimes   = x$EndTime,
+        labels     = x$Label
     )
   }
 )
diff --git a/R/PointTier-constructor.R b/R/PointTier-constructor.R
index 7b260e5..bf4b5ec 100755
--- a/R/PointTier-constructor.R
+++ b/R/PointTier-constructor.R
@@ -7,7 +7,7 @@ NULL
 #' An S4 generic and S4 methods for creating an \code{\link[=PointTier-class]{PointTier}}
 #' object.
 #'
-#' @param praatText A character vector, the lines of text from a
+#' @param x A character vector, the lines of text from a
 #'   \code{.TextGrid} file that define a PointTier.
 #' @param ... optional arguments for multiple dispatch (in development).
 #' @return A \code{\link[=PointTier-class]{PointTier}} object. Values for the
@@ -19,7 +19,7 @@ NULL
 #' @importFrom methods setGeneric
 setGeneric(
   name = 'PointTier',
-  def  = function(praatText, ...)
+  def  = function(x, ...)
     standardGeneric('PointTier')
 )
 
@@ -28,13 +28,33 @@ setGeneric(
 #' @importFrom methods setMethod new
 setMethod(
   f   = 'PointTier',
-  sig = c(praatText = 'character'),
-  def = function(praatText)
+  sig = c(x = 'character'),
+  def = function(x)
     # Initialize the TextTier object.
     new(Class = 'PointTier',
-        name       = .TierName(praatText),
-        number     = .TierNumber(praatText),
-        times      = .PointTimes(praatText),
-        labels     = .PointLabels(praatText)
+        name       = .TierName(x),
+        number     = .TierNumber(x),
+        times      = .PointTimes(x),
+        labels     = .PointLabels(x)
+    )
+)
+
+
+#' @rdname PointTier-constructor
+#' @importFrom methods setMethod new
+setMethod(
+  f   = 'PointTier',
+  sig = c(x = 'data.frame'),
+  def = function(x)
+    # TODO: Check if TierName column exists exists
+    # TODO: Check if TierNumber col exists
+    # TODO: Check if StartTime col exists
+    # TODO: Check if Label col exists
+    # Initialize the TextTier object.
+    new(Class = 'PointTier',
+        name       = x$TierName[1],
+        number     = x$TierNumber[1],
+        times      = x$StartTime,
+        labels     = x$Label
     )
 )
diff --git a/R/TextGrid-constructor.R b/R/TextGrid-constructor.R
index 3e364dc..7a28860 100755
--- a/R/TextGrid-constructor.R
+++ b/R/TextGrid-constructor.R
@@ -16,6 +16,9 @@ NULL
 #'  argument is the path to a \code{.TextGrid} file. Otherwise, the
 #'  \code{textGrid} argument is assumed to be a character vector whose
 #'  elements are the lines of some \code{.TextGrid} file.
+#' @section Details for signature \code{c(textGrid = 'data.frame')}:
+#'  If \code{textGrid} is a data.frame it is tried to create a TextGrid object 
+#'  from it.
 #' @name TextGrid-constructor
 #' @aliases TextGrid
 #' @seealso \code{\link{TextGrid-class}}, \code{\link{TextGrid-accessors}}
@@ -45,3 +48,33 @@ setMethod(
         endTime = .TextGridTime(.textgrid, pattern = '^xmax')
     )
   })
+
+#' @rdname TextGrid-constructor
+#' @export
+#' @importFrom methods setMethod new
+setMethod(
+  f   = 'TextGrid',
+  sig = c(textGrid = 'data.frame'),
+  def = function(textGrid, startTime = 0, endTime = NULL) {
+    # TODO: Check if TierNumber column exists
+    # TODO: Check if TierType column exists
+    .tiers <- .DataFrame2TierObjects(textGrid)
+    .lastAnnotation <- max(
+      sapply(.tiers, function(x) {
+        if (inherits(x, 'PointTier')) { 
+          return(max(pointTimes(x)))
+        } else if (inherits(x, 'IntervalTier')) {
+          return(max(intervalEndTimes(x)))
+        }
+      })
+    )
+    endTime <- max(endTime, .lastAnnotation)
+    new(Class = 'TextGrid',
+        .tiers,
+        startTime = startTime,
+        endTime = endTime
+    )
+  })
+
+
+  
\ No newline at end of file
diff --git a/R/TextGrid-utilities.R b/R/TextGrid-utilities.R
index 0cfd593..04a8a2d 100755
--- a/R/TextGrid-utilities.R
+++ b/R/TextGrid-utilities.R
@@ -53,3 +53,32 @@ NULL
   names(.tier_objects) <- .TierName(praatText)
   return(.tier_objects)
 }
+
+
+# convert a TextGrid data frame to a list of IntervalTier and PointTier objects 
+.DataFrame2TierObjects <- function(x) {
+  # TODO: Check if TierType and TierNumber exist
+  lapply(split(x, x$TierNumber), function(t) {
+    .tierType <- t$TierType[1]
+    if (.tierType == "IntervalTier") {
+      return(IntervalTier(t))
+    } else if (.tierType == "PointTier") {
+      return(PointTier(t))
+    }
+  })
+}
+
+# Check a data frame for compatibility with TextGrid constructor, report 
+# issues, make educated guesses to rename and clean columns where possible
+.CleanTextGridDataFrame <- function(x) {
+  # TODO: check if all necessary columns exist
+  # TODO: fill gaps between StarTime/EndTime with NA
+  y <- x %>% 
+    group_by(TierType, TierNumber) %>% 
+    mutate(StartTime = EndTime,
+           EndTime = lag(EndTime),
+           Label = NA)
+  
+  return(y)
+}
+
diff --git a/R/writeTextGrid.R b/R/writeTextGrid.R
new file mode 100644
index 0000000..4872d5a
--- /dev/null
+++ b/R/writeTextGrid.R
@@ -0,0 +1,114 @@
+#' @include Tier-class.R IntervalTier-class.R PointTier-class.R TextGrid-class.R
+NULL
+
+
+#' Write Praat-compatible TextGrid.
+#' 
+#' Convert a \code{TextGrid} object to a Praat-compatible character string and 
+#' (optionally) write it to a file.
+#' 
+#' @param x A \code{TextGrid} object to be written. 
+#' @param path Either a character string naming a file to write to, a connection 
+#' open for writing, or \code{NULL} (default) for no output. When writing to 
+#' file or connection, \code{path} is passed on as the \code{con} argument to 
+#' \code{\link{writeLines}}
+#' @param ... Additional arguments passed on to \code{\link{writeLines}} 
+#' when writing to a file or connection.
+#' @return A character vector, Each element is one row of the TextGrid file.
+#' 
+#' @seealso \code{\link{TextGrid-class}}
+#' @name writeTextGrid
+#' @export
+writeTextGrid <- function(x, path = NULL, ...)  {
+  .tiers <- x@.Data
+  .nTiers <- length(.tiers)
+
+  .header <- c(
+            'File type = "ooTextFile"',
+            'Object class = "TextGrid"',
+            '',
+    sprintf('xmin = %g', textGridStartTime(x)),
+    sprintf('xmax = %g', textGridEndTime(x)),
+            'tiers? <exists>',
+    sprintf('size = %g', .nTiers),
+            'item []:'
+  )
+  .tiers <- sapply(.tiers, function(t) {
+    if (inherits(t, "IntervalTier")) { 
+      return(writeIntervalTier(t)) 
+    } else if (inherits(t, "PointTier")) {
+      return(writePointTier(t))
+    }
+  })
+  
+  .out <- c(.header, unlist(.tiers))
+  if (!is.null(path)) {
+    writeLines(.out, con = path, ...) 
+    return(invisible(.out))
+  } else {
+    return(.out)
+  }
+}
+
+
+# convert IntervalTier object into a Praat-compatible character vector and 
+# (optionally) write it to a file.
+writeIntervalTier <- function(x, path = NULL, ...) {
+  .tierStart <- min(intervalStartTimes(x))
+  .tierEnd <- max(intervalEndTimes(x))
+  .labels <- replace(intervalLabels(x), is.na(intervalLabels(x)), "")
+  .tierLen <- length(.labels)
+  
+  .header <- c(
+    sprintf('    item[%d]:', tierNumber(x)),
+            '        class = "IntervalTier"',
+    sprintf('        name = "%s"', tierName(x)),
+    sprintf('        xmin = %g', .tierStart),
+    sprintf('        xmax = %g', .tierEnd),
+    sprintf('        intervals: size = %d', .tierLen)
+  )
+  .annotations <- mapply(function(startTime, endTime, label) {
+    c(sprintf('            xmin = %g', startTime),
+      sprintf('            xmax = %g', endTime),
+      sprintf('            text = "%s"', label))
+  }, intervalStartTimes(x), intervalEndTimes(x), .labels, SIMPLIFY = T)
+  
+  .out <- c(.header, .annotations)
+  if (!is.null(path)) {
+    writeLines(.out, con = path, ...) 
+    return(invisible(.out))
+  } else {
+    return(.out)
+  }
+}
+
+
+# convert PointTier object into a Praat-compatible character vector and 
+# (optionally) write it to a file.
+writePointTier <- function(x, path = NULL, ...) {
+  .tierStart <- min(pointTimes(x))
+  .tierEnd <- max(pointTimes(x))
+  .labels <- replace(pointLabels(x), is.na(pointLabels(x)), "")
+  .tierLen <- length(.labels)
+  
+  .header <- c(
+    sprintf('    item[%d]:', tierNumber(x)),
+            '        class = "TextTier"',
+    sprintf('        name = "%s"', tierName(x)),
+    sprintf('        xmin = %g', .tierStart),
+    sprintf('        xmax = %g', .tierEnd),
+    sprintf('        points: size = %d', .tierLen)
+  )
+  .annotations <- mapply(function(time, label) {
+    c(sprintf('            number = %g', time),
+      sprintf('            mark = "%s"', label))
+  }, pointTimes(x), .labels, SIMPLIFY = T)
+  
+  .out <- c(.header, .annotations)
+  if (!is.null(path)) {
+    writeLines(.out, con = path, ...) 
+    return(invisible(.out))
+  } else {
+    return(.out)
+  }
+}
\ No newline at end of file
diff --git a/README.md b/README.md
index 8c57f4d..11a1b2b 100755
--- a/README.md
+++ b/README.md
@@ -98,6 +98,17 @@ as.data.frame(textgrid)
 # 11          3   Events    PointTier     2      8.25    8.25 voicingOff
 ```
 
+#### Convert a data.frame to a TextGrid object
+```r
+df <- as.data.frame(textgrid)
+TextGrid(df)
+```
+
+#### Write a TextGrid object to a Praat-compatible .TextGrid file.
+```r
+writeTextGrid(textgrid, path = 'test_out.TextGrid')
+```
+
 ## Details on S4 classes
 
 The textgRid package defines four S4 classes, whose slots and accessors are 
diff --git a/man/IntervalTier-accessors.Rd b/man/IntervalTier-accessors.Rd
index 0e4d2b4..c75f184 100755
--- a/man/IntervalTier-accessors.Rd
+++ b/man/IntervalTier-accessors.Rd
@@ -2,9 +2,9 @@
 % Please edit documentation in R/IntervalTier-accessors.R
 \name{IntervalTier-accessors}
 \alias{IntervalTier-accessors}
+\alias{intervalStartTimes}
 \alias{intervalEndTimes}
 \alias{intervalLabels}
-\alias{intervalStartTimes}
 \title{Access the slots of IntervalTier objects.}
 \usage{
 intervalStartTimes(tier)
@@ -24,4 +24,3 @@ object.
 \code{\link{IntervalTier-class}},
   \code{\link{IntervalTier-constructor}}, \code{\link{Tier-accessors}}
 }
-
diff --git a/man/IntervalTier-class.Rd b/man/IntervalTier-class.Rd
index d7b4333..78a7358 100755
--- a/man/IntervalTier-class.Rd
+++ b/man/IntervalTier-class.Rd
@@ -26,9 +26,9 @@ IntervalTier.}
 \item{\code{labels}}{A character vector, the labels of the intervals in the
 IntervalTier.}
 }}
+
 \seealso{
 \code{\link{IntervalTier-constructor}},
   \code{\link{IntervalTier-accessors}}, \code{\link{TextGrid-class}},
   \code{\link{Tier-class}}
 }
-
diff --git a/man/IntervalTier-constructor.Rd b/man/IntervalTier-constructor.Rd
index cd06747..2e93633 100755
--- a/man/IntervalTier-constructor.Rd
+++ b/man/IntervalTier-constructor.Rd
@@ -2,20 +2,23 @@
 % Please edit documentation in R/IntervalTier-constructor.R
 \docType{methods}
 \name{IntervalTier-constructor}
+\alias{IntervalTier-constructor}
 \alias{IntervalTier}
 \alias{IntervalTier,character-method}
-\alias{IntervalTier-constructor}
+\alias{IntervalTier,data.frame-method}
 \title{Create an instance of the IntervalTier class.}
 \usage{
-IntervalTier(praatText, ...)
+IntervalTier(x, ...)
 
-\S4method{IntervalTier}{character}(praatText)
+\S4method{IntervalTier}{character}(x)
+
+\S4method{IntervalTier}{data.frame}(x, startTime = 0, endTime = NULL)
 }
 \arguments{
+\item{...}{optional arguments for multiple dispatch (in development).}
+
 \item{praatText}{A character vector, the lines of text from a
 \code{.TextGrid} file that define an IntervalTier.}
-
-\item{...}{optional arguments for multiple dispatch (in development).}
 }
 \value{
 A \code{\link[=IntervalTier-class]{IntervalTier}} object. Values for the
@@ -29,4 +32,3 @@ object.
 \seealso{
 \code{\link{IntervalTier-class}}, \code{\link{IntervalTier-accessors}}
 }
-
diff --git a/man/PointTier-accessors.Rd b/man/PointTier-accessors.Rd
index 8a5e6c4..0c36ed8 100755
--- a/man/PointTier-accessors.Rd
+++ b/man/PointTier-accessors.Rd
@@ -2,8 +2,8 @@
 % Please edit documentation in R/PointTier-accessors.R
 \name{PointTier-accessors}
 \alias{PointTier-accessors}
-\alias{pointLabels}
 \alias{pointTimes}
+\alias{pointLabels}
 \title{Access the slots of PointTier objects.}
 \usage{
 pointTimes(tier)
@@ -21,4 +21,3 @@ object.
 \code{\link{PointTier-class}},
   \code{\link{PointTier-constructor}}, \code{\link{Tier-accessors}}
 }
-
diff --git a/man/PointTier-class.Rd b/man/PointTier-class.Rd
index 4c19506..1f3fdf0 100755
--- a/man/PointTier-class.Rd
+++ b/man/PointTier-class.Rd
@@ -21,9 +21,9 @@ A point's label is typically the annotation of some event in waveform data
 
 \item{\code{labels}}{A character vector, the labels of the points in the PointTier.}
 }}
+
 \seealso{
 \code{\link{PointTier-constructor}},
   \code{\link{PointTier-accessors}}, \code{\link{TextGrid-class}},
   \code{\link{Tier-class}}
 }
-
diff --git a/man/PointTier-constructor.Rd b/man/PointTier-constructor.Rd
index 3c7e6fb..2f6c2c9 100755
--- a/man/PointTier-constructor.Rd
+++ b/man/PointTier-constructor.Rd
@@ -2,17 +2,20 @@
 % Please edit documentation in R/PointTier-constructor.R
 \docType{methods}
 \name{PointTier-constructor}
+\alias{PointTier-constructor}
 \alias{PointTier}
 \alias{PointTier,character-method}
-\alias{PointTier-constructor}
+\alias{PointTier,data.frame-method}
 \title{Create an instance of the PointTier class.}
 \usage{
-PointTier(praatText, ...)
+PointTier(x, ...)
 
-\S4method{PointTier}{character}(praatText)
+\S4method{PointTier}{character}(x)
+
+\S4method{PointTier}{data.frame}(x)
 }
 \arguments{
-\item{praatText}{A character vector, the lines of text from a
+\item{x}{A character vector, the lines of text from a
 \code{.TextGrid} file that define a PointTier.}
 
 \item{...}{optional arguments for multiple dispatch (in development).}
@@ -29,4 +32,3 @@ object.
 \seealso{
 \code{\link{PointTier-class}}, \code{\link{PointTier-accessors}}
 }
-
diff --git a/man/TextGrid-accessors.Rd b/man/TextGrid-accessors.Rd
index 3dcf711..9a0dfbb 100755
--- a/man/TextGrid-accessors.Rd
+++ b/man/TextGrid-accessors.Rd
@@ -2,8 +2,8 @@
 % Please edit documentation in R/TextGrid-accessors.R
 \name{TextGrid-accessors}
 \alias{TextGrid-accessors}
-\alias{textGridEndTime}
 \alias{textGridStartTime}
+\alias{textGridEndTime}
 \title{Access the slots of TextGrid objects.}
 \usage{
 textGridStartTime(textGrid)
@@ -21,4 +21,3 @@ object.
 \code{\link{TextGrid-class}},
   \code{\link{TextGrid-constructor}}
 }
-
diff --git a/man/TextGrid-class.Rd b/man/TextGrid-class.Rd
index 6340288..3d0e9cc 100755
--- a/man/TextGrid-class.Rd
+++ b/man/TextGrid-class.Rd
@@ -21,9 +21,9 @@ A \code{TextGrid} object is essentially a list of
 
 \item{\code{endTime}}{A numeric, the end time of the TextGrid.}
 }}
+
 \seealso{
 \code{\link{TextGrid-constructor}},
   \code{\link{TextGrid-accessors}}, \code{\link{IntervalTier-class}},
   \code{\link{PointTier-class}}
 }
-
diff --git a/man/TextGrid-constructor.Rd b/man/TextGrid-constructor.Rd
index a80f3a8..a45daa3 100755
--- a/man/TextGrid-constructor.Rd
+++ b/man/TextGrid-constructor.Rd
@@ -2,14 +2,17 @@
 % Please edit documentation in R/TextGrid-constructor.R
 \docType{methods}
 \name{TextGrid-constructor}
+\alias{TextGrid-constructor}
 \alias{TextGrid}
 \alias{TextGrid,character-method}
-\alias{TextGrid-constructor}
+\alias{TextGrid,data.frame-method}
 \title{Create an instance of the TextGrid class.}
 \usage{
 TextGrid(textGrid, ...)
 
 \S4method{TextGrid}{character}(textGrid)
+
+\S4method{TextGrid}{data.frame}(textGrid, startTime = 0, endTime = NULL)
 }
 \arguments{
 \item{textGrid}{A character vector}
@@ -31,7 +34,13 @@ object.
  \code{textGrid} argument is assumed to be a character vector whose
  elements are the lines of some \code{.TextGrid} file.
 }
+
+\section{Details for signature \code{c(textGrid = 'data.frame')}}{
+
+ If \code{textGrid} is a data.frame it is tried to create a TextGrid object 
+ from it.
+}
+
 \seealso{
 \code{\link{TextGrid-class}}, \code{\link{TextGrid-accessors}}
 }
-
diff --git a/man/Tier-accessors.Rd b/man/Tier-accessors.Rd
index d2ee169..a94ac24 100755
--- a/man/Tier-accessors.Rd
+++ b/man/Tier-accessors.Rd
@@ -19,4 +19,3 @@ Get the values of slots in a \code{\link[=Tier-class]{Tier}} object.
 \seealso{
 \code{\link{Tier-class}}
 }
-
diff --git a/man/Tier-class.Rd b/man/Tier-class.Rd
index 771e0d7..cdd4574 100755
--- a/man/Tier-class.Rd
+++ b/man/Tier-class.Rd
@@ -2,8 +2,8 @@
 % Please edit documentation in R/Tier-class.R
 \docType{class}
 \name{Tier-class}
-\alias{Tier}
 \alias{Tier-class}
+\alias{Tier}
 \title{Tier S4 class for Praat TextGrids.}
 \description{
 The \code{Tier} class is extended by the \code{\link[=PointTier-class]{PointTier}}
@@ -18,8 +18,8 @@ to both subtypes of tier-like object.
 
 \item{\code{number}}{An integer, the number of the Tier within the TextGrid.}
 }}
+
 \seealso{
 \code{\link{IntervalTier-class}}, \code{\link{PointTier-class}},
   \code{\link{TextGrid-class}}, \code{\link{Tier-accessors}}
 }
-
diff --git a/man/findIntervals.Rd b/man/findIntervals.Rd
index a9675d0..c692a38 100755
--- a/man/findIntervals.Rd
+++ b/man/findIntervals.Rd
@@ -45,4 +45,3 @@ only at the time given by \code{at}.
 \seealso{
 \code{\link{IntervalTier-class}}, \code{\link{grep}}
 }
-
diff --git a/man/findPoints.Rd b/man/findPoints.Rd
index 1961387..c3efb34 100755
--- a/man/findPoints.Rd
+++ b/man/findPoints.Rd
@@ -36,4 +36,3 @@ time range, whose labels match a pattern.
 \seealso{
 \code{\link{PointTier-class}}, \code{\link{grep}}
 }
-
diff --git a/man/textgRid-as.data.frame.Rd b/man/textgRid-as.data.frame.Rd
index de21c71..998e5ba 100755
--- a/man/textgRid-as.data.frame.Rd
+++ b/man/textgRid-as.data.frame.Rd
@@ -1,10 +1,13 @@
 % Generated by roxygen2: do not edit by hand
 % Please edit documentation in R/as.data.frame.R
 \name{textgRid-as.data.frame}
+\alias{textgRid-as.data.frame}
+\alias{as.data.frame.IntervalTier}
+\alias{as.data.frame.PointTier}
+\alias{as.data.frame.TextGrid}
 \alias{as.data.frame.IntervalTier}
 \alias{as.data.frame.PointTier}
 \alias{as.data.frame.TextGrid}
-\alias{textgRid-as.data.frame}
 \title{Coerce to a data.frame.}
 \usage{
 \method{as.data.frame}{IntervalTier}(x, row.names = NULL, optional = FALSE,
@@ -46,4 +49,3 @@ to a \code{data.frame}.
 \code{findIntervals()} and \code{findPoints()}, respectively. Only intervals
 and points that have contentful, non-empty labels are returned after coercion.
 }
-
diff --git a/man/textgRid-length.Rd b/man/textgRid-length.Rd
index 700ea25..7d42e2a 100755
--- a/man/textgRid-length.Rd
+++ b/man/textgRid-length.Rd
@@ -1,9 +1,11 @@
 % Generated by roxygen2: do not edit by hand
 % Please edit documentation in R/length.R
 \name{textgRid-length}
+\alias{textgRid-length}
+\alias{length.IntervalTier}
+\alias{length.PointTier}
 \alias{length.IntervalTier}
 \alias{length.PointTier}
-\alias{textgRid-length}
 \title{Length of an IntervalTier or PointTier}
 \usage{
 \method{length}{IntervalTier}(x)
@@ -31,4 +33,3 @@ of the \code{labels}-vector is returned; otherwise, \code{NULL} is returned.
 have the same length. If so, the length of the \code{labels}-vector is
 returned; otherwise, \code{NULL} is returned.
 }
-
diff --git a/man/writeTextGrid.Rd b/man/writeTextGrid.Rd
new file mode 100644
index 0000000..99999ce
--- /dev/null
+++ b/man/writeTextGrid.Rd
@@ -0,0 +1,29 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/writeTextGrid.R
+\name{writeTextGrid}
+\alias{writeTextGrid}
+\title{Write Praat-compatible TextGrid.}
+\usage{
+writeTextGrid(x, path = NULL, ...)
+}
+\arguments{
+\item{x}{A \code{TextGrid} object to be written.}
+
+\item{path}{Either a character string naming a file to write to, a connection 
+open for writing, or \code{NULL} (default) for no output. When writing to 
+file or connection, \code{path} is passed on as the \code{con} argument to 
+\code{\link{writeLines}}}
+
+\item{...}{Additional arguments passed on to \code{\link{writeLines}} 
+when writing to a file or connection.}
+}
+\value{
+A character vector, Each element is one row of the TextGrid file.
+}
+\description{
+Convert a \code{TextGrid} object to a Praat-compatible character string and 
+(optionally) write it to a file.
+}
+\seealso{
+\code{\link{TextGrid-class}}
+}
diff --git a/tests/testthat/test-TextGrid.R b/tests/testthat/test-TextGrid.R
index 261eb89..2b89e92 100755
--- a/tests/testthat/test-TextGrid.R
+++ b/tests/testthat/test-TextGrid.R
@@ -208,3 +208,35 @@ test_that('as.data.frame.TextGrid() can override default row names', {
     expected = .labels
   )
 })
+
+
+test_that('TextGrid() of data.frame returns a TextGrid', {
+  .textgrid_in <- TextGrid('../test.TextGrid')
+  .textgrid_out <- TextGrid(as.data.frame(.textgrid_in))
+  expect_s4_class(.textgrid_out, 'TextGrid')
+})
+
+
+test_that('TextGrid() of data.frame returns a TextGrid', {
+  .textgrid_in <- TextGrid('../test.TextGrid')
+  .textgrid_out <- TextGrid(as.data.frame(.textgrid_in))
+  expect_s4_class(.textgrid_out, 'TextGrid')
+})
+
+
+test_that('as.data.frame(TextGrid(as.data.frame(x))) equals x', {
+  .df_in <- as.data.frame(TextGrid('../test.TextGrid'))
+  .df_out <- as.data.frame(TextGrid(.df_in))
+  expect_equal(.df_in, .df_out)
+})
+
+
+test_that('TextGrid(as.data.frame(x))  equals x', {
+  .textgrid_in <- TextGrid('../test.TextGrid')
+  .textgrid_out <- TextGrid(as.data.frame(.textgrid_in))
+  expect_equal(.textgrid_in@.Data, .textgrid_out@.Data)
+  expect_equal(textGridStartTime(.textgrid_in), 
+               textGridStartTime(.textgrid_out))
+  expect_equal(textGridEndTime(.textgrid_in), 
+               textGridEndTime(.textgrid_out))
+})
diff --git a/tests/testthat/test-writeTextGrid.R b/tests/testthat/test-writeTextGrid.R
new file mode 100644
index 0000000..a3da7d2
--- /dev/null
+++ b/tests/testthat/test-writeTextGrid.R
@@ -0,0 +1,66 @@
+library(textgRid)
+context('TextGrid')
+
+
+test_that('writeTextGrid() returns valid TextGrid character vector', {
+  .fin <- '../test.TextGrid'
+  .textgrid <- TextGrid(.fin)
+  .textgrid_lines <- writeTextGrid(.textgrid)
+  
+  expect_s4_class(
+    object = TextGrid(.textgrid_lines),
+    class  = 'TextGrid'
+  )
+})
+
+
+test_that('writeTextGrid() output is identical to input TextGrid', {
+  .fin <- '../test.TextGrid'
+  .textgrid_in <- TextGrid(.fin)
+  .textgrid_lines <- writeTextGrid(.textgrid_in)
+  .textgrid_out <- TextGrid(.textgrid_lines)
+  
+  expect_identical(.textgrid_out, .textgrid_in)
+})
+
+
+test_that('writeTextGrid() can write to file', {
+  .fin <- '../test.TextGrid'
+  .fout <- '../test_out.TextGrid'
+  .textgrid_in <- TextGrid(.fin)
+  writeTextGrid(.textgrid_in, path = .fout)
+  .textgrid_out <- TextGrid(.fout)
+  
+  expect_identical(.textgrid_out, .textgrid_in)
+  file.remove(.fout)
+})
+
+
+test_that('writeIntervalTier() can write to file', {
+  .fin <- '../test.TextGrid'
+  .fout <- '../test_out.TextGrid'
+  .textgrid_in <- TextGrid(.fin)
+  .tier <- .textgrid_in@.Data[[1]] # an ItervalTier
+  
+  .tier_in <- writeIntervalTier(.tier)
+  writeIntervalTier(.tier, path = .fout)
+  .tier_out <- readLines(.fout)
+  
+  expect_identical(.tier_in, .tier_out)
+  file.remove(.fout)
+})
+
+
+test_that('writePointTier() can write to file', {
+  .fin <- '../test.TextGrid'
+  .fout <- '../test_out.TextGrid'
+  .textgrid_in <- TextGrid(.fin)
+  .tier <- .textgrid_in@.Data[[3]] # a PointTier
+  
+  .tier_in <- writePointTier(.tier)
+  writePointTier(.tier, path = .fout)
+  .tier_out <- readLines(.fout)
+  
+  expect_identical(.tier_in, .tier_out)
+  file.remove(.fout)
+})
\ No newline at end of file