diff --git a/d3.layout.js b/d3.layout.js
index 6cc1d716..2708cafb 100644
--- a/d3.layout.js
+++ b/d3.layout.js
@@ -1030,9 +1030,9 @@ d3.layout.hierarchy = function() {
         node = d3_layout_hierarchyInline ? data : {data: data};
     node.depth = depth;
     nodes.push(node);
-    if (childs) {
+    if (childs && (n = childs.length)) {
       var i = -1,
-          n = childs.length,
+          n,
           c = node.children = [],
           v = 0,
           j = depth + 1;
@@ -1054,9 +1054,9 @@ d3.layout.hierarchy = function() {
   function revalue(node, depth) {
     var children = node.children,
         v = 0;
-    if (children) {
+    if (children && (n = children.length)) {
       var i = -1,
-          n = children.length,
+          n,
           j = depth + 1;
       while (++i < n) v += revalue(children[i], j);
     } else if (value) {
@@ -1096,6 +1096,12 @@ d3.layout.hierarchy = function() {
     return root;
   };
 
+  // If the new API is used, enabling inlining.
+  hierarchy.nodes = function(d) {
+    d3_layout_hierarchyInline = true;
+    return (hierarchy.nodes = hierarchy)(d);
+  };
+
   return hierarchy;
 };
 
@@ -1354,9 +1360,10 @@ d3.layout.cluster = function() {
 
     // First walk, computing the initial x & y values.
     d3_layout_treeVisitAfter(root, function(node) {
-      if (node.children) {
-        node.x = d3_layout_clusterX(node.children);
-        node.y = d3_layout_clusterY(node.children);
+      var children = node.children;
+      if (children && children.length) {
+        node.x = d3_layout_clusterX(children);
+        node.y = d3_layout_clusterY(children);
       } else {
         node.x = previousNode ? x += separation(node, previousNode) : 0;
         node.y = 0;
@@ -1408,12 +1415,15 @@ function d3_layout_clusterX(children) {
 
 function d3_layout_clusterLeft(node) {
   var children = node.children;
-  return children ? d3_layout_clusterLeft(children[0]) : node;
+  return children && children.length
+    ? d3_layout_clusterLeft(children[0]) : node;
 }
 
 function d3_layout_clusterRight(node) {
-  var children = node.children;
-  return children ? d3_layout_clusterRight(children[children.length - 1]) : node;
+  var children = node.children,
+      n;
+  return children && (n = children.length)
+    ? d3_layout_clusterRight(children[n - 1]) : node;
 }
 // Node-link tree diagram using the Reingold-Tilford "tidy" algorithm
 d3.layout.tree = function() {
diff --git a/d3.layout.min.js b/d3.layout.min.js
index 0deabfac..3dbdacb0 100644
--- a/d3.layout.min.js
+++ b/d3.layout.min.js
@@ -1 +1 @@
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diff --git a/src/layout/cluster.js b/src/layout/cluster.js
index e030f45b..00fa06f5 100644
--- a/src/layout/cluster.js
+++ b/src/layout/cluster.js
@@ -14,9 +14,10 @@ d3.layout.cluster = function() {
 
     // First walk, computing the initial x & y values.
     d3_layout_treeVisitAfter(root, function(node) {
-      if (node.children) {
-        node.x = d3_layout_clusterX(node.children);
-        node.y = d3_layout_clusterY(node.children);
+      var children = node.children;
+      if (children && children.length) {
+        node.x = d3_layout_clusterX(children);
+        node.y = d3_layout_clusterY(children);
       } else {
         node.x = previousNode ? x += separation(node, previousNode) : 0;
         node.y = 0;
@@ -68,10 +69,13 @@ function d3_layout_clusterX(children) {
 
 function d3_layout_clusterLeft(node) {
   var children = node.children;
-  return children ? d3_layout_clusterLeft(children[0]) : node;
+  return children && children.length
+    ? d3_layout_clusterLeft(children[0]) : node;
 }
 
 function d3_layout_clusterRight(node) {
-  var children = node.children;
-  return children ? d3_layout_clusterRight(children[children.length - 1]) : node;
+  var children = node.children,
+      n;
+  return children && (n = children.length)
+    ? d3_layout_clusterRight(children[n - 1]) : node;
 }
diff --git a/src/layout/hierarchy.js b/src/layout/hierarchy.js
index f6c074bc..23abd0f9 100644
--- a/src/layout/hierarchy.js
+++ b/src/layout/hierarchy.js
@@ -10,9 +10,9 @@ d3.layout.hierarchy = function() {
         node = d3_layout_hierarchyInline ? data : {data: data};
     node.depth = depth;
     nodes.push(node);
-    if (childs) {
+    if (childs && (n = childs.length)) {
       var i = -1,
-          n = childs.length,
+          n,
           c = node.children = [],
           v = 0,
           j = depth + 1;
@@ -34,9 +34,9 @@ d3.layout.hierarchy = function() {
   function revalue(node, depth) {
     var children = node.children,
         v = 0;
-    if (children) {
+    if (children && (n = children.length)) {
       var i = -1,
-          n = children.length,
+          n,
           j = depth + 1;
       while (++i < n) v += revalue(children[i], j);
     } else if (value) {
@@ -76,6 +76,12 @@ d3.layout.hierarchy = function() {
     return root;
   };
 
+  // If the new API is used, enabling inlining.
+  hierarchy.nodes = function(d) {
+    d3_layout_hierarchyInline = true;
+    return (hierarchy.nodes = hierarchy)(d);
+  };
+
   return hierarchy;
 };
 
diff --git a/test/layout/cluster-test.js b/test/layout/cluster-test.js
new file mode 100644
index 00000000..885f8c11
--- /dev/null
+++ b/test/layout/cluster-test.js
@@ -0,0 +1,39 @@
+require("../env");
+require("../../d3");
+require("../../d3.layout");
+
+var vows = require("vows"),
+    assert = require("assert");
+
+var suite = vows.describe("d3.layout.cluster");
+
+suite.addBatch({
+  "cluster": {
+    topic: d3.layout.cluster,
+    "can handle an empty children array": function(cluster) {
+      assert.deepEqual(cluster.nodes({value: 1, children: [{value: 1, children: []}, {value: 1}]}).map(layout), [
+        {value: 1, depth: 0, x: 0.5,  y: 0},
+        {value: 1, depth: 1, x: 0.25, y: 1},
+        {value: 1, depth: 1, x: 0.75, y: 1}
+      ]);
+    },
+    "can handle zero-valued nodes": function(cluster) {
+      assert.deepEqual(cluster.nodes({value: 0, children: [{value: 0}, {value: 1}]}).map(layout), [
+        {value: 0, depth: 0, x: 0.5,  y: 0},
+        {value: 0, depth: 1, x: 0.25, y: 1},
+        {value: 1, depth: 1, x: 0.75, y: 1}
+      ]);
+    }
+  }
+});
+
+function layout(node) {
+  return {
+    value: node.value,
+    depth: node.depth,
+    x: node.x,
+    y: node.y
+  };
+}
+
+suite.export(module);
diff --git a/test/layout/hierarchy-test.js b/test/layout/hierarchy-test.js
new file mode 100644
index 00000000..46b9fea8
--- /dev/null
+++ b/test/layout/hierarchy-test.js
@@ -0,0 +1,36 @@
+require("../env");
+require("../../d3");
+require("../../d3.layout");
+
+var vows = require("vows"),
+    assert = require("assert");
+
+var suite = vows.describe("d3.layout.hierarchy");
+
+suite.addBatch({
+  "hierarchy": {
+    topic: d3.layout.hierarchy,
+    "doesn't overwrite the value of a node that has an empty children array": function(hierarchy) {
+      var nodes = hierarchy.nodes({value: 1, children: []});
+      assert.deepEqual(nodes, [
+        {children: [], depth: 0, value: 1}
+      ]);
+      hierarchy.revalue(nodes[0]);
+      assert.deepEqual(nodes, [
+        {children: [], depth: 0, value: 1}
+      ]);
+    },
+    "a valueless node that has an empty children array gets a value of 0": function(hierarchy) {
+      var nodes = hierarchy.nodes({children: []});
+      assert.deepEqual(nodes, [
+        {children: [], depth: 0, value: 0}
+      ]);
+      hierarchy.revalue(nodes[0]);
+      assert.deepEqual(nodes, [
+        {children: [], depth: 0, value: 0}
+      ]);
+    }
+  }
+});
+
+suite.export(module);
diff --git a/test/layout/partition-test.js b/test/layout/partition-test.js
index 1b34eef2..929fb890 100644
--- a/test/layout/partition-test.js
+++ b/test/layout/partition-test.js
@@ -14,7 +14,7 @@ suite.addBatch({
     },
     "ignores zero values": function(partition) {
       var p = partition().size([3, 3]);
-      assert.deepEqual(p({children: [{value: 1}, {value: 0}, {value: 2}, {children: [{value: 0}, {value: 0}]}]}).map(metadata), [
+      assert.deepEqual(p.nodes({children: [{value: 1}, {value: 0}, {value: 2}, {children: [{value: 0}, {value: 0}]}]}).map(metadata), [
         {x: 0, y: 0, dx: 3, dy: 1},
         {x: 2, y: 1, dx: 1, dy: 1},
         {x: 3, y: 1, dx: 0, dy: 1},
@@ -23,6 +23,17 @@ suite.addBatch({
         {x: 3, y: 2, dx: 0, dy: 1},
         {x: 3, y: 2, dx: 0, dy: 1}
       ]);
+    },
+    "can handle an empty children array": function(partition) {
+      var p = partition();
+      assert.deepEqual(p.nodes({children: []}).map(metadata), [
+        {x: 0, y: 0, dx: 1, dy: 1}
+      ]);
+      assert.deepEqual(p.nodes({children: [{children: []}, {value: 1}]}).map(metadata), [
+        {x: 0, y: 0,   dx: 1, dy: 0.5},
+        {x: 1, y: 0.5, dx: 0, dy: 0.5},
+        {x: 0, y: 0.5, dx: 1, dy: 0.5}
+      ]);
     }
   }
 });
diff --git a/test/layout/treemap-test.js b/test/layout/treemap-test.js
index 7318789b..0e4e17ec 100644
--- a/test/layout/treemap-test.js
+++ b/test/layout/treemap-test.js
@@ -164,6 +164,16 @@ suite.addBatch({
             {"value": 1189}
           ]}).map(layout);
       assert.equal(nodes.filter(function(n) { return n.dx < 0 || n.dy < 0; }).length, 0);
+    },
+    "can handle an empty children array": function(treemap) {
+      assert.deepEqual(treemap().nodes({children: []}).map(layout), [
+        {x: 0, y: 0, dx: 1, dy: 1}
+      ]);
+      assert.deepEqual(treemap().nodes({children: [{children: []}, {value: 1}]}).map(layout), [
+        {x: 0, y: 0, dx: 1, dy: 1},
+        {x: 0, y: 0, dx: 0, dy: 1},
+        {x: 0, y: 0, dx: 1, dy: 1}
+      ]);
     }
   }
 });