diff --git a/CHANGELOG.md b/CHANGELOG.md
index cd10a4f9..1f544dcd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+### Added
+
+- Implement `Sum` for `CpuQuantity` and `MemoryQuantity` ([#634]).
+
+[#634]: https://github.com/stackabletech/operator-rs/pull/634
+
 ## [0.46.0] - 2023-08-08
 
 ### Changed
diff --git a/src/cpu.rs b/src/cpu.rs
index 8f780724..005d32e5 100644
--- a/src/cpu.rs
+++ b/src/cpu.rs
@@ -1,4 +1,5 @@
 use std::{
+    iter::Sum,
     ops::{Add, AddAssign, Div, Mul, MulAssign},
     str::FromStr,
 };
@@ -151,6 +152,12 @@ impl MulAssign<f32> for CpuQuantity {
     }
 }
 
+impl Sum for CpuQuantity {
+    fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {
+        iter.fold(CpuQuantity { millis: 0 }, CpuQuantity::add)
+    }
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
diff --git a/src/memory.rs b/src/memory.rs
index 2c7c0733..851f2293 100644
--- a/src/memory.rs
+++ b/src/memory.rs
@@ -356,7 +356,7 @@ impl Add<MemoryQuantity> for MemoryQuantity {
     }
 }
 
-impl Sum<MemoryQuantity> for MemoryQuantity {
+impl Sum for MemoryQuantity {
     fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {
         iter.fold(
             MemoryQuantity {