diff --git a/README.md b/README.md
index 94296d15..71362fe9 100644
--- a/README.md
+++ b/README.md
@@ -89,7 +89,11 @@ A reference to the data associated with this node, as specified to the [construc
 
 <a name="node_depth" href="#node_depth">#</a> <i>node</i>.<b>depth</b>
 
-The depth of the node: zero for the root node, and increasing by one for each subsequent generation.
+The depth of the node: zero for the root node, and increasing by one for each descendant generation.
+
+<a name="node_height" href="#node_height">#</a> <i>node</i>.<b>height</b>
+
+The height of the node: zero for any leaf node, and increasing by one for each ancestor generation.
 
 <a name="node_parent" href="#node_parent">#</a> <i>node</i>.<b>parent</b>
 
@@ -140,7 +144,6 @@ Similarly, to sort nodes by descending height (greatest distance from any descen
 ```js
 root
     .sum(function(d) { return d.value; })
-    .eachBefore(function(d) { var h = 0; do d.height = h; while ((d = d.parent) && (d.height < ++h)); })
     .sort(function(a, b) { return b.height - a.height || b.value - a.value; });
 ```
 
@@ -495,6 +498,7 @@ This returns:
 {
   "id": "Eve",
   "depth": 0,
+  "height": 2,
   "data": {
     "id": "Eve",
     "parentId": ""
@@ -503,6 +507,7 @@ This returns:
     {
       "id": "Cain",
       "depth": 1,
+      "height": 0,
       "parent": [Circular],
       "data": {
         "id": "Cain",
@@ -512,6 +517,7 @@ This returns:
     {
       "id": "Seth",
       "depth": 1,
+      "height": 1,
       "parent": [Circular],
       "data": {
         "id": "Seth",
@@ -521,6 +527,7 @@ This returns:
         {
           "id": "Enos",
           "depth": 2,
+          "height": 0,
           "parent": [Circular],
           "data": {
             "id": "Enos",
@@ -530,6 +537,7 @@ This returns:
         {
           "id": "Noam",
           "depth": 2,
+          "height": 0,
           "parent": [Circular],
           "data": {
              "id": "Noam",
@@ -541,6 +549,7 @@ This returns:
     {
       "id": "Abel",
       "depth": 1,
+      "height": 0,
       "parent": [Circular],
       "data": {
         "id": "Abel",
@@ -550,6 +559,7 @@ This returns:
     {
       "id": "Awan",
       "depth": 1,
+      "height": 1,
       "parent": [Circular],
       "data": {
         "id": "Awan",
@@ -559,6 +569,7 @@ This returns:
         {
           "id": "Enoch",
           "depth": 2,
+          "height": 0,
           "parent": [Circular],
           "data": {
              "id": "Enoch",
@@ -570,6 +581,7 @@ This returns:
     {
       "id": "Azura",
       "depth": 1,
+      "height": 0,
       "parent": [Circular],
       "data": {
         "id": "Azura",
diff --git a/src/hierarchy/index.js b/src/hierarchy/index.js
index 5d560856..f7c0edfb 100644
--- a/src/hierarchy/index.js
+++ b/src/hierarchy/index.js
@@ -30,18 +30,27 @@ export default function hierarchy(data) {
     }
   }
 
-  return root;
+  return root.eachBefore(computeHeight);
 }
 
 function node_copy() {
-  return hierarchy(this).eachBefore(function(node) {
-    node.data = node.data.data;
-  });
+  return hierarchy(this).eachBefore(copyData);
+}
+
+function copyData(node) {
+  node.data = node.data.data;
+}
+
+export function computeHeight(node) {
+  var height = 0;
+  do node.height = height;
+  while ((node = node.parent) && (node.height < ++height));
 }
 
 export function Node(data) {
   this.data = data;
-  this.depth = 0;
+  this.depth =
+  this.height = 0;
   this.parent = null;
 }
 
diff --git a/src/stratify.js b/src/stratify.js
index 10db8b2b..88e48d13 100644
--- a/src/stratify.js
+++ b/src/stratify.js
@@ -1,5 +1,5 @@
 import {required} from "./accessors";
-import {Node} from "./hierarchy/index";
+import {Node, computeHeight} from "./hierarchy/index";
 
 var keyPrefix = "$", // Protect against keys like “__proto__”.
     preroot = {depth: -1};
@@ -53,7 +53,7 @@ export default function() {
 
     if (!root) throw new Error("no root");
     root.parent = preroot;
-    root.eachBefore(function(node) { node.depth = node.parent.depth + 1; --n; });
+    root.eachBefore(function(node) { node.depth = node.parent.depth + 1; --n; }).eachBefore(computeHeight);
     root.parent = null;
     if (n > 0) throw new Error("cycle");
 
diff --git a/test/stratify-test.js b/test/stratify-test.js
index b7481f1a..e1daaf83 100644
--- a/test/stratify-test.js
+++ b/test/stratify-test.js
@@ -20,16 +20,19 @@ tape("stratify(data) returns the root node", function(test) {
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 2,
     data: {id: "a"},
     children: [
       {
         id: "aa",
         depth: 1,
+        height: 1,
         data: {id: "aa", parentId: "a"},
         children: [
           {
             id: "aaa",
             depth: 2,
+            height: 0,
             data: {id: "aaa", parentId: "aa"}
           }
         ]
@@ -37,6 +40,7 @@ tape("stratify(data) returns the root node", function(test) {
       {
         id: "ab",
         depth: 1,
+        height: 0,
         data: {id: "ab", parentId: "a"}
       }
     ]
@@ -55,16 +59,19 @@ tape("stratify(data) does not require the data to be in topological order", func
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 2,
     data: {id: "a"},
     children: [
       {
         id: "aa",
         depth: 1,
+        height: 1,
         data: {id: "aa", parentId: "a"},
         children: [
           {
             id: "aaa",
             depth: 2,
+            height: 0,
             data: {id: "aaa", parentId: "aa"}
           }
         ]
@@ -72,6 +79,7 @@ tape("stratify(data) does not require the data to be in topological order", func
       {
         id: "ab",
         depth: 1,
+        height: 0,
         data: {id: "ab", parentId: "a"}
       }
     ]
@@ -90,21 +98,25 @@ tape("stratify(data) preserves the input order of siblings", function(test) {
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 2,
     data: {id: "a"},
     children: [
       {
         id: "ab",
         depth: 1,
+        height: 0,
         data: {id: "ab", parentId: "a"}
       },
       {
         id: "aa",
         depth: 1,
+        height: 1,
         data: {id: "aa", parentId: "a"},
         children: [
           {
             id: "aaa",
             depth: 2,
+            height: 0,
             data: {id: "aaa", parentId: "aa"}
           }
         ]
@@ -125,16 +137,19 @@ tape("stratify(data) treats an empty parentId as the root", function(test) {
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 2,
     data: {id: "a", parentId: ""},
     children: [
       {
         id: "aa",
         depth: 1,
+        height: 1,
         data: {id: "aa", parentId: "a"},
         children: [
           {
             id: "aaa",
             depth: 2,
+            height: 0,
             data: {id: "aaa", parentId: "aa"}
           }
         ]
@@ -142,6 +157,7 @@ tape("stratify(data) treats an empty parentId as the root", function(test) {
       {
         id: "ab",
         depth: 1,
+        height: 0,
         data: {id: "ab", parentId: "a"}
       }
     ]
@@ -159,16 +175,19 @@ tape("stratify(data) does not treat a falsy but non-empty parentId as the root",
   test.deepEqual(noparent(root), {
     id: "0",
     depth: 0,
+    height: 1,
     data: {id: 0, parentId: null},
     children: [
       {
         id: "1",
         depth: 1,
+        height: 0,
         data: {id: 1, parentId: 0}
       },
       {
         id: "2",
         depth: 1,
+        height: 0,
         data: {id: 2, parentId: 0}
       }
     ]
@@ -213,14 +232,17 @@ tape("stratify(data) allows the id to be undefined for leaf nodes", function(tes
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 1,
     data: {id: "a"},
     children: [
       {
         depth: 1,
+        height: 0,
         data: {parentId: "a"}
       },
       {
         depth: 1,
+        height: 0,
         data: {parentId: "a"}
       }
     ]
@@ -245,10 +267,12 @@ tape("stratify(data) allows the id to be undefined for leaf nodes", function(tes
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 1,
     data: {id: "a"},
     children: [
       {
         depth: 1,
+        height: 0,
         data: o
       }
     ]
@@ -269,16 +293,19 @@ tape("stratify.id(id) observes the specified id function", function(test) {
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 2,
     data: {foo: "a"},
     children: [
       {
         id: "aa",
         depth: 1,
+        height: 1,
         data: {foo: "aa", parentId: "a"},
         children: [
           {
             id: "aaa",
             depth: 2,
+            height: 0,
             data: {foo: "aaa", parentId:"aa" }
           }
         ]
@@ -286,6 +313,7 @@ tape("stratify.id(id) observes the specified id function", function(test) {
       {
         id: "ab",
         depth: 1,
+        height: 0,
         data: {foo: "ab", parentId:"a" }
       }
     ]
@@ -313,16 +341,19 @@ tape("stratify.parentId(id) observes the specified parent id function", function
   test.deepEqual(noparent(root), {
     id: "a",
     depth: 0,
+    height: 2,
     data: {id: "a"},
     children: [
       {
         id: "aa",
         depth: 1,
+        height: 1,
         data: {id: "aa", foo: "a"},
         children: [
           {
             id: "aaa",
             depth: 2,
+            height: 0,
             data: {id: "aaa", foo: "aa"}
           }
         ]
@@ -330,6 +361,7 @@ tape("stratify.parentId(id) observes the specified parent id function", function
       {
         id: "ab",
         depth: 1,
+        height: 0,
         data: {id: "ab", foo: "a"}
       }
     ]
diff --git a/test/treemap/flare-test.js b/test/treemap/flare-test.js
index 1d71b749..02dd62b3 100644
--- a/test/treemap/flare-test.js
+++ b/test/treemap/flare-test.js
@@ -50,6 +50,7 @@ function test(input, expected, tile) {
         delete node.parent;
         delete node.data;
         delete node._squarify;
+        delete node.height;
         if (node.children) node.children.forEach(visit);
       })(actual);