diff --git a/css/20_map.css b/css/20_map.css
index b43c664e86..a0d82d1c4e 100644
--- a/css/20_map.css
+++ b/css/20_map.css
@@ -336,3 +336,117 @@ g.vertex.highlighted .shadow {
 .surface.tr g.vertex.related.only .shadow {
     stroke: #68f;
 }
+
+/* highlight-edited means 'visual diff activated'
+ 'graphedited' class means that a geometric (dark green) change has occurred.
+ 'tagedited' means that a tagging change has occurred. 
+ if both are true, the 'graphedited' class supersedes 'tagedited'. 
+
+ /*Vertex-related visual diffs*/ 
+.highlight-edited g.points > circle.vertex.graphedited {
+    color: rgb(87, 201, 44);
+    stroke: #333;
+    stroke-width: 1;
+    stroke-opacity: .5;
+    fill-opacity: 1;
+}
+.highlight-edited g.points > circle.vertex.tagedited {
+    color: rgb(160, 231, 134);
+    stroke: #fff;
+    stroke-width: 2;
+    stroke-opacity: .5;
+    fill-opacity: 1;
+}
+
+/*Line-related visual diffs*/ 
+/*Make the edited stroke line thin so that the original road color can show around it.*/
+.highlight-edited g.lines > path.line.graphedited,
+.highlight-edited g.areas > path.line.graphedited {
+    color: rgb(87, 201, 44);
+    stroke-width: 3 !important;
+    stroke-opacity: 1;
+}
+
+/*Make the stroke in whole-road graph edits thin and less apparent. */
+.highlight-edited g.linegroup.line-stroke > path.way.line.stroke.graphedited {
+    stroke: rgb(87, 201, 44);
+    stroke-width: 3 !important;
+    stroke-opacity: 1;
+}
+
+/*Make the casing around tag edits wide enough to be a bit more visible. */
+.highlight-edited g.linegroup.line-casing > path.way.line.casing.tagedited {
+    stroke: rgb(87, 201, 44) !important;
+    stroke-width: 12 !important;
+    stroke-opacity: 1;
+}
+
+.low-zoom.highlight-edited g.linegroup.line-casing > path.way.line.casing.tagedited {
+    stroke-width: 10 !important;
+}
+
+/* Area-related visual diffs */ 
+.highlight-edited g.areagroup.area-fill > path.way.area.fill.graphedited {
+    stroke-width: 45px; 
+    stroke-opacity: .5; 
+}
+
+.highlight-edited g.areagroup.area-stroke > path.way.area.stroke.graphedited {
+    stroke: rgb(87, 201, 44) !important;
+    stroke-width: 5 !important; 
+}
+
+.highlight-edited g.areagroup.area-stroke > path.way.area.stroke.tagedited {
+    stroke: rgb(160, 231, 134) !important;
+    stroke-width: 3 !important; 
+}
+
+.highlight-edited g.areagroup.area-shadow > path.way.area.shadow.graphedited {
+    fill: rgb(87, 201, 44);
+    opacity: .2;  
+}
+
+.highlight-edited g.areagroup.area-shadow > path.way.area.shadow.tagedited {
+    fill: rgb(87, 201, 44);
+    opacity: .1;  
+}
+
+.highlight-edited g.areagroup.area-fill > path.way.area.fill.tagedited {
+    stroke-width: 30;   
+}
+
+.low-zoom.highlight-edited.fill-wireframe g.areagroup.area-stroke > path.way.area.stroke.tagedited {
+    stroke-dasharray: 7; 
+    stroke: rgb(87, 201, 44) !important;
+    stroke-width: 4px;
+}
+
+.low-zoom.highlight-edited g.areagroup.area-stroke > path.way.area.stroke.tagedited {
+    stroke: rgb(160, 231, 134);
+    stroke-width: 40; 
+    stroke-dasharray: 25 !important; 
+    stroke-opacity: 1 !important;
+}
+
+.highlight-edited.fill-wireframe g.linegroup.line-stroke > path.way.line.stroke.tagedited {
+    stroke: rgb(160, 231, 134);
+    stroke-width: 10 !important;
+    stroke-dasharray: 25 !important; 
+    stroke-opacity: 1 !important;
+}
+
+.highlight-edited.fill-wireframe g.areagroup.area-shadow > path.way.area.shadow.graphedited,
+.highlight-edited.fill-wireframe g.areagroup.area-shadow > path.way.area.shadow.tagedited {
+    fill-opacity: .05; 
+}
+
+/*for low zoom levels, make the wireframe view 'tag edit' dashed line finer.*/
+.low-zoom.highlight-edited.fill-wireframe g.linegroup.line-stroke > path.way.line.stroke.tagedited {
+    stroke-dasharray: 7 !important;
+} 
+
+/*In wireframe mode, restrain the stroke width to something barely wider than normal.*/
+.fill-wireframe.highlight-edited g.lines > path.line.graphedited, .fill-wireframe.highlight-edited g.linegroup.line-stroke > path.way.line.stroke.tagedited,
+.fill-wireframe.highlight-edited g.areas > path.area.graphedited, .fill-wireframe.highlight-edited g.linegroup.line-stroke > path.way.area.stroke.tagedited {
+    stroke-width: 2 !important;
+}
diff --git a/data/core.yaml b/data/core.yaml
index 44fbebb8a4..0f6014a41f 100644
--- a/data/core.yaml
+++ b/data/core.yaml
@@ -612,6 +612,10 @@ en:
         title: Custom Map Data
         zoom: Zoom to data
     fill_area: Fill Areas
+    highlight_way_edits:
+      description: Highlight edited nodes and segments attached to those nodes in ways
+      tooltip: Highlight unsaved edits.
+      key: G
     map_features: Map Features
     autohidden: "These features have been automatically hidden because too many would be shown on the screen.  You can zoom in to edit them."
     osmhidden: "These features have been automatically hidden because the OpenStreetMap layer is hidden."
@@ -1885,6 +1889,7 @@ en:
         wireframe: "Toggle wireframe mode"
         osm_data: "Toggle OpenStreetMap data"
         minimap: "Toggle minimap"
+        highlight_way_edits: "Highlight unsaved edits"
       selecting:
         title: "Selecting features"
         select_one: "Select a single feature"
diff --git a/data/shortcuts.json b/data/shortcuts.json
index ce189797c9..5cba3f4c33 100644
--- a/data/shortcuts.json
+++ b/data/shortcuts.json
@@ -82,6 +82,10 @@
             {
               "shortcuts": ["background.minimap.key"],
               "text": "shortcuts.browsing.display_options.minimap"
+            }, 
+            {
+              "shortcuts": ["map_data.highlight_way_edits.key"],
+              "text": "shortcuts.browsing.display_options.highlight_way_edits"
             }
           ]
         },
diff --git a/modules/svg/areas.js b/modules/svg/areas.js
index b76c46e336..90e7357c5f 100644
--- a/modules/svg/areas.js
+++ b/modules/svg/areas.js
@@ -3,9 +3,10 @@ import { bisector as d3_bisector } from 'd3-array';
 import { osmEntity, osmIsOldMultipolygonOuterMember } from '../osm';
 import { svgPath, svgSegmentWay } from './helpers';
 import { svgTagClasses } from './tag_classes';
+import _isEqual from 'lodash-es/isEqual';
+import _omit from 'lodash-es/omit';
 import { svgTagPattern } from './tag_pattern';
 
-
 export function svgAreas(projection, context) {
 
 
@@ -75,6 +76,7 @@ export function svgAreas(projection, context) {
         var path = svgPath(projection, graph, true);
         var areas = {};
         var multipolygon;
+        var base = context.history().base();
 
         for (var i = 0; i < entities.length; i++) {
             var entity = entities[i];
@@ -158,12 +160,32 @@ export function svgAreas(projection, context) {
             }
         }
 
+
+        var graphEditClass = function(d) {
+            if (d.type !== 'way'){
+                return '';
+            }
+            var graphEdited = d.nodes.some(function(n) {
+                if (!base.entities[n]) {
+                    return true;
+                }
+                var result = !_isEqual(_omit(graph.entities[n], ['tags', 'v']), _omit(base.entities[n], ['tags', 'v']));
+                return result;
+            });
+
+            if (graphEdited){
+                return 'graphedited';
+            }
+
+            return (!_isEqual(graph.entities[d.id].tags, base.entities[d.id].tags)) ? 'tagedited' : '';
+        };
+
         paths = paths.enter()
             .insert('path', sortedByArea)
             .merge(paths)
             .each(function(entity) {
                 var layer = this.parentNode.__data__;
-                this.setAttribute('class', entity.type + ' area ' + layer + ' ' + entity.id);
+                this.setAttribute('class', entity.type + ' area ' + layer + ' ' + graphEditClass(entity) + ' ' + entity.id);
 
                 if (layer === 'fill') {
                     this.setAttribute('clip-path', 'url(#' + entity.id + '-clippath)');
diff --git a/modules/svg/lines.js b/modules/svg/lines.js
index 1e1d360527..4ac285ade1 100644
--- a/modules/svg/lines.js
+++ b/modules/svg/lines.js
@@ -8,7 +8,10 @@ import { svgTagClasses } from './tag_classes';
 import { osmEntity, osmOldMultipolygonOuterMember } from '../osm';
 import { utilArrayFlatten, utilArrayGroupBy } from '../util';
 import { utilDetect } from '../util/detect';
-
+import _isEqual from 'lodash-es/isEqual';
+import _transform from 'lodash-es/transform';
+import _omit from 'lodash-es/omit'; 
+import _isObject from 'lodash-es/isObject'; 
 
 export function svgLines(projection, context) {
     var detected = utilDetect();
@@ -34,6 +37,7 @@ export function svgLines(projection, context) {
         var nopeClass = context.getDebug('target') ? 'red ' : 'nocolor ';
         var getPath = svgPath(projection).geojson;
         var activeID = context.activeID();
+        var base = context.history().base();
 
         // The targets and nopes will be MultiLineString sub-segments of the ways
         var data = { targets: [], nopes: [] };
@@ -55,13 +59,24 @@ export function svgLines(projection, context) {
         targets.exit()
             .remove();
 
+        var graphEditClass = function(d) {
+            return d.properties.nodes.some(function(n) {
+                if (!base.entities[n.id]) {
+                    return true; 
+                }                
+                var result = !_isEqual(_omit(graph.entities[n.id], ['tags', 'v']), _omit(base.entities[n.id], ['tags', 'v'])); 
+                return result; 
+            }) ? ' graphedited ': '';
+        };
+
         // enter/update
         targets.enter()
             .append('path')
             .merge(targets)
             .attr('d', getPath)
-            .attr('class', function(d) { return 'way line target target-allowed ' + targetClass + d.id; });
-
+            .attr('class', function(d) {
+                return 'way line target target-allowed ' + targetClass + d.id + graphEditClass(d);
+            });
 
         // NOPE
         var nopeData = data.nopes.filter(getPath);
@@ -78,11 +93,14 @@ export function svgLines(projection, context) {
             .append('path')
             .merge(nopes)
             .attr('d', getPath)
-            .attr('class', function(d) { return 'way line target target-nope ' + nopeClass + d.id; });
+            .attr('class', function(d) { 
+                return 'way line target target-nope ' + nopeClass + d.id + graphEditClass(d); 
+            });
     }
 
 
     function drawLines(selection, graph, entities, filter) {
+        var base = context.history().base();
 
         function waystack(a, b) {
             var selected = context.selectedIDs();
@@ -95,6 +113,27 @@ export function svgLines(projection, context) {
         }
 
 
+        // Class for styling currently tag-edited lines, not changes to geometry
+        var tagEditClass = function(d) {
+            var result = graph.entities[d.id] && base.entities[d.id] &&  !_isEqual(graph.entities[d.id].tags, base.entities[d.id].tags); 
+
+            return result ? 
+            ' tagedited ' :  ''; 
+        };
+
+
+        // Class for styling currently geometry-edited lines
+        var graphEditClass = function(d) {
+            if (!base.entities[d.id]) {
+                return ' graphedited '; 
+            }
+
+            var result = graph.entities[d.id] && base.entities[d.id] &&  !_isEqual(_omit(graph.entities[d.id], ['tags', 'v']), _omit(base.entities[d.id], ['tags', 'v'])); 
+
+            return result ? ' graphedited ' :  ''; 
+        };
+
+
         function drawLineGroup(selection, klass, isSelected) {
             // Note: Don't add `.selected` class in draw modes
             var mode = context.mode();
@@ -122,7 +161,7 @@ export function svgLines(projection, context) {
                     }
 
                     var oldMPClass = oldMultiPolygonOuters[d.id] ? 'old-multipolygon ' : '';
-                    return prefix + ' ' + klass + ' ' + selectedClass + oldMPClass + d.id;
+                    return prefix + ' ' + klass + ' ' + selectedClass + oldMPClass + graphEditClass(d) + tagEditClass(d) + d.id;
                 })
                 .call(svgTagClasses())
                 .merge(lines)
diff --git a/modules/svg/vertices.js b/modules/svg/vertices.js
index 1c48a64aee..3410b99e96 100644
--- a/modules/svg/vertices.js
+++ b/modules/svg/vertices.js
@@ -3,7 +3,8 @@ import { select as d3_select } from 'd3-selection';
 import { geoScaleToZoom } from '../geo';
 import { osmEntity } from '../osm';
 import { svgPassiveVertex, svgPointTransform } from './helpers';
-
+import _isEqual from 'lodash-es/isEqual';
+import _omit from 'lodash-es/omit'; 
 
 export function svgVertices(projection, context) {
     var radiuses = {
@@ -194,6 +195,9 @@ export function svgVertices(projection, context) {
         var getTransform = svgPointTransform(projection).geojson;
         var activeID = context.activeID();
         var data = { targets: [], nopes: [] };
+        var base = context.history().base();
+        var radius = 3;
+        var interestingNodeRadius = 4.5;
 
         entities.forEach(function(node) {
             if (activeID === node.id) return;   // draw no target on the activeID
@@ -223,6 +227,16 @@ export function svgVertices(projection, context) {
             }
         });
 
+        // Class for styling currently edited vertices
+        var editClass = function(d) {
+            //If it doesn't exist in the base graph, it's new geometry. 
+            if (!base.entities[d.id] || !_isEqual(_omit(graph.entities[d.id], ['tags', 'v']), _omit(base.entities[d.id], ['tags', 'v']))) {
+                return ' graphedited ';
+            } else if (!_isEqual(graph.entities[d.id].tags, base.entities[d.id].tags)) {
+                return ' tagedited ';
+            }
+            return '';
+        };
 
         // Targets allow hover and vertex snapping
         var targets = selection.selectAll('.vertex.target-allowed')
@@ -233,12 +247,22 @@ export function svgVertices(projection, context) {
         targets.exit()
             .remove();
 
+        var threeFourths = function (num) {
+            return (Math.round(3 * num) / 4).toFixed(2); 
+        }; 
         // enter/update
         targets.enter()
             .append('circle')
-            .attr('r', function(d) { return (_radii[d.id] || radiuses.shadow[3]); })
+            .attr('r', function(d) {
+                return isEditedEnt(d, base, graph) && threeFourths(_radii[d.id])
+                  || _radii[d.id] 
+                  || radiuses.shadow[3];
+            })
             .merge(targets)
-            .attr('class', function(d) { return 'node vertex target target-allowed ' + targetClass + d.id; })
+            .attr('class', function(d) {
+                return 'node vertex target target-allowed '
+                + targetClass + d.id + editClass(d);
+            })
             .attr('transform', getTransform);
 
 
@@ -272,6 +296,12 @@ export function svgVertices(projection, context) {
     }
 
 
+    function isEditedEnt(entity, base, head) {
+        return head.entities[entity.id] !== base.entities[entity.id] ||
+            !_isEqual(head.entities[entity.id].tags, base.entities[entity.id].tags);
+    }
+
+
     function getSiblingAndChildVertices(ids, graph, wireframe, zoom) {
         var results = {};
 
@@ -324,6 +354,7 @@ export function svgVertices(projection, context) {
         var zoom = geoScaleToZoom(projection.scale());
         var mode = context.mode();
         var isMoving = mode && /^(add|draw|drag|move|rotate)/.test(mode.id);
+        var base = context.history().base();
 
         var drawLayer = selection.selectAll('.layer-osm.points .points-group.vertices');
         var touchLayer = selection.selectAll('.layer-touch.points');
@@ -347,7 +378,8 @@ export function svgVertices(projection, context) {
 
             // a vertex of some importance..
             } else if (geometry === 'vertex' &&
-                (entity.hasInterestingTags() || entity.isEndpoint(graph) || entity.isConnected(graph))) {
+                (entity.hasInterestingTags() || entity.isEndpoint(graph) || entity.isConnected(graph)
+                || isEditedEnt(entity, base, graph))) {
                 _currPersistent[entity.id] = entity;
                 keep = true;
             }
diff --git a/modules/ui/map_data.js b/modules/ui/map_data.js
index 6abfc4d8d2..156f3ad8d4 100644
--- a/modules/ui/map_data.js
+++ b/modules/ui/map_data.js
@@ -86,6 +86,13 @@ export function uiMapData(context) {
     }
 
 
+    function toggleHighlightEdited() {
+        d3_event.preventDefault();
+        var surface = context.surface();
+        surface.classed('highlight-edited', !surface.classed('highlight-edited'));
+    }
+
+
     function showsLayer(which) {
         var layer = layers.layer(which);
         if (layer) {
@@ -881,7 +888,8 @@ export function uiMapData(context) {
                 d3_event.preventDefault();
                 d3_event.stopPropagation();
                 toggleLayer('osm');
-            });
+            })
+            .on(t('map_data.highlight_way_edits.key'), toggleHighlightEdited);
     };
 
     return uiMapData;