diff --git a/modules/actions/straighten.js b/modules/actions/straighten.js
index 686d59fa6..b849bcafb 100644
--- a/modules/actions/straighten.js
+++ b/modules/actions/straighten.js
@@ -51,8 +51,11 @@ export function actionStraighten(selectedIDs, projection) {
 
         // If user selected 2 nodes to straighten between, then slice nodes array to those nodes
         if (selectedNodes.length) {
-            var startEndPoints = [nodes.indexOf(graph.entity(selectedNodes[0])), nodes.indexOf(graph.entity(selectedNodes[1]))].sort();
-            nodes = nodes.slice(startEndPoints[0], startEndPoints[1]+1);
+            startNode = nodes.indexOf(graph.entity(selectedNodes[0]));
+            endNode = nodes.indexOf(graph.entity(selectedNodes[1]));
+            var sortedStartEnd = [startNode, endNode].sort();
+            
+            nodes = nodes.slice(sortedStartEnd[0], sortedStartEnd[1]+1);
         }
 
         return nodes;
diff --git a/modules/operations/straighten.js b/modules/operations/straighten.js
index 86b1bb3aa..112746445 100644
--- a/modules/operations/straighten.js
+++ b/modules/operations/straighten.js
@@ -41,7 +41,7 @@ export function operationStraighten(selectedIDs, context) {
             endNodes.push(entity.nodes[entity.nodes.length-1]);
         }
 
-        if (_uniq(nodes).length <= 2 || selectedNodes.length > 2) return false;
+        if (_uniq(nodes).length <= 2 || ![0,2].includes(selectedNodes.length)) return false;
 
         // Ensure all ways are connected (i.e. only one unique start point and one unique end point)
         if (_difference(startNodes, endNodes).length !== 1 ||
diff --git a/test/spec/operations/straighten.js b/test/spec/operations/straighten.js
index 7ee8a8e5d..86d341771 100644
--- a/test/spec/operations/straighten.js
+++ b/test/spec/operations/straighten.js
@@ -92,5 +92,20 @@ describe('iD.operationStraighten', function () {
             var result = iD.operationStraighten(['n2', 'n7', 'w4', 'w1', 'w3', 'w2'], fakeContext.graph()).available();
             expect(result).to.be.ok;
         });
+
+        it('is not available for nodes not on selected ways', function () {
+            var result = iD.operationStraighten(['w5', 'n4', 'n11'], fakeContext.graph()).available();
+            expect(result).to.be.not.ok;
+        });
+
+        it('is not available for one selected node', function () {
+            var result = iD.operationStraighten(['w5', 'n9'], fakeContext.graph()).available();
+            expect(result).to.be.not.ok;
+        });
+
+        it('is not available for more than two selected nodes', function () {
+            var result = iD.operationStraighten(['w5', 'n9', 'n11', 'n12'], fakeContext.graph()).available();
+            expect(result).to.be.not.ok;
+        });
     });
 });