diff --git a/blocks/procedures.js b/blocks/procedures.js
index f6b25bcd6..7eb785509 100644
--- a/blocks/procedures.js
+++ b/blocks/procedures.js
@@ -120,8 +120,11 @@ Blockly.Blocks['procedures_defnoreturn'] = {
     // The params field is deterministic based on the mutation,
     // no need to fire a change event.
     Blockly.Events.disable();
-    this.setFieldValue(paramString, 'PARAMS');
-    Blockly.Events.enable();
+    try {
+      this.setFieldValue(paramString, 'PARAMS');
+    } finally {
+      Blockly.Events.enable();
+    }
   },
   /**
    * Create XML to represent the argument inputs.
@@ -589,8 +592,11 @@ Blockly.Blocks['procedures_callnoreturn'] = {
         // The argument name field is deterministic based on the mutation,
         // no need to fire a change event.
         Blockly.Events.disable();
-        field.setValue(this.arguments_[i]);
-        Blockly.Events.enable();
+        try {
+          field.setValue(this.arguments_[i]);
+        } finally {
+          Blockly.Events.enable();
+        }
       } else {
         // Add new input.
         field = new Blockly.FieldLabel(this.arguments_[i]);
diff --git a/core/block.js b/core/block.js
index 92b533be8..d4640f275 100644
--- a/core/block.js
+++ b/core/block.js
@@ -204,39 +204,42 @@ Blockly.Block.prototype.dispose = function(healStack) {
   }
   Blockly.Events.disable();
 
-  // This block is now at the top of the workspace.
-  // Remove this block from the workspace's list of top-most blocks.
-  if (this.workspace) {
-    this.workspace.removeTopBlock(this);
-    // Remove from block database.
-    delete this.workspace.blockDB_[this.id];
-    this.workspace = null;
-  }
-
-  // Just deleting this block from the DOM would result in a memory leak as
-  // well as corruption of the connection database.  Therefore we must
-  // methodically step through the blocks and carefully disassemble them.
-
-  // First, dispose of all my children.
-  for (var i = this.childBlocks_.length - 1; i >= 0; i--) {
-    this.childBlocks_[i].dispose(false);
-  }
-  // Then dispose of myself.
-  // Dispose of all inputs and their fields.
-  for (var i = 0, input; input = this.inputList[i]; i++) {
-    input.dispose();
-  }
-  this.inputList.length = 0;
-  // Dispose of any remaining connections (next/previous/output).
-  var connections = this.getConnections_(true);
-  for (var i = 0; i < connections.length; i++) {
-    var connection = connections[i];
-    if (connection.isConnected()) {
-      connection.disconnect();
+  try {
+    // This block is now at the top of the workspace.
+    // Remove this block from the workspace's list of top-most blocks.
+    if (this.workspace) {
+      this.workspace.removeTopBlock(this);
+      // Remove from block database.
+      delete this.workspace.blockDB_[this.id];
+      this.workspace = null;
     }
-    connections[i].dispose();
+
+    // Just deleting this block from the DOM would result in a memory leak as
+    // well as corruption of the connection database.  Therefore we must
+    // methodically step through the blocks and carefully disassemble them.
+
+    // First, dispose of all my children.
+    for (var i = this.childBlocks_.length - 1; i >= 0; i--) {
+      this.childBlocks_[i].dispose(false);
+    }
+    // Then dispose of myself.
+    // Dispose of all inputs and their fields.
+    for (var i = 0, input; input = this.inputList[i]; i++) {
+      input.dispose();
+    }
+    this.inputList.length = 0;
+    // Dispose of any remaining connections (next/previous/output).
+    var connections = this.getConnections_(true);
+    for (var i = 0; i < connections.length; i++) {
+      var connection = connections[i];
+      if (connection.isConnected()) {
+        connection.disconnect();
+      }
+      connections[i].dispose();
+    }
+  } finally {
+    Blockly.Events.enable();
   }
-  Blockly.Events.enable();
 };
 
 /**
diff --git a/core/block_svg.js b/core/block_svg.js
index ee70a93d1..1e3024a50 100644
--- a/core/block_svg.js
+++ b/core/block_svg.js
@@ -156,8 +156,11 @@ Blockly.BlockSvg.prototype.select = function() {
     oldId = Blockly.selected.id;
     // Unselect any previously selected block.
     Blockly.Events.disable();
-    Blockly.selected.unselect();
-    Blockly.Events.enable();
+    try {
+      Blockly.selected.unselect();
+    } finally {
+      Blockly.Events.enable();
+    }
   }
   var event = new Blockly.Events.Ui(null, 'selected', oldId, this.id);
   event.workspaceId = this.workspace.id;
@@ -999,11 +1002,14 @@ Blockly.BlockSvg.prototype.dispose = function(healStack, animate) {
   this.rendered = false;
 
   Blockly.Events.disable();
-  var icons = this.getIcons();
-  for (var i = 0; i < icons.length; i++) {
-    icons[i].dispose();
+  try {
+    var icons = this.getIcons();
+    for (var i = 0; i < icons.length; i++) {
+      icons[i].dispose();
+    }
+  } finally {
+    Blockly.Events.enable();
   }
-  Blockly.Events.enable();
   Blockly.BlockSvg.superClass_.dispose.call(this, healStack);
 
   goog.dom.removeNode(this.svgGroup_);
diff --git a/core/contextmenu.js b/core/contextmenu.js
index af92cf6e2..462ad0b2c 100644
--- a/core/contextmenu.js
+++ b/core/contextmenu.js
@@ -126,17 +126,20 @@ Blockly.ContextMenu.hide = function() {
 Blockly.ContextMenu.callbackFactory = function(block, xml) {
   return function() {
     Blockly.Events.disable();
-    var newBlock = Blockly.Xml.domToBlock(xml, block.workspace);
-    // Move the new block next to the old block.
-    var xy = block.getRelativeToSurfaceXY();
-    if (block.RTL) {
-      xy.x -= Blockly.SNAP_RADIUS;
-    } else {
-      xy.x += Blockly.SNAP_RADIUS;
+    try {
+      var newBlock = Blockly.Xml.domToBlock(xml, block.workspace);
+      // Move the new block next to the old block.
+      var xy = block.getRelativeToSurfaceXY();
+      if (block.RTL) {
+        xy.x -= Blockly.SNAP_RADIUS;
+      } else {
+        xy.x += Blockly.SNAP_RADIUS;
+      }
+      xy.y += Blockly.SNAP_RADIUS * 2;
+      newBlock.moveBy(xy.x, xy.y);
+    } finally {
+      Blockly.Events.enable();
     }
-    xy.y += Blockly.SNAP_RADIUS * 2;
-    newBlock.moveBy(xy.x, xy.y);
-    Blockly.Events.enable();
     if (Blockly.Events.isEnabled() && !newBlock.isShadow()) {
       Blockly.Events.fire(new Blockly.Events.Create(newBlock));
     }
diff --git a/core/flyout.js b/core/flyout.js
index e8aa2f872..52eebc7c1 100644
--- a/core/flyout.js
+++ b/core/flyout.js
@@ -844,8 +844,11 @@ Blockly.Flyout.prototype.createBlockFunc_ = function(originBlock) {
       return;
     }
     Blockly.Events.disable();
-    var block = flyout.placeNewBlock_(originBlock);
-    Blockly.Events.enable();
+    try {
+      var block = flyout.placeNewBlock_(originBlock);
+    } finally {
+      Blockly.Events.enable();
+    }
     if (Blockly.Events.isEnabled()) {
       Blockly.Events.setGroup(true);
       Blockly.Events.fire(new Blockly.Events.Create(block));
diff --git a/core/workspace_svg.js b/core/workspace_svg.js
index d857bdf21..251d5ef10 100644
--- a/core/workspace_svg.js
+++ b/core/workspace_svg.js
@@ -535,51 +535,54 @@ Blockly.WorkspaceSvg.prototype.paste = function(xmlBlock) {
   }
   Blockly.terminateDrag_();  // Dragging while pasting?  No.
   Blockly.Events.disable();
-  var block = Blockly.Xml.domToBlock(xmlBlock, this);
-  // Move the duplicate to original position.
-  var blockX = parseInt(xmlBlock.getAttribute('x'), 10);
-  var blockY = parseInt(xmlBlock.getAttribute('y'), 10);
-  if (!isNaN(blockX) && !isNaN(blockY)) {
-    if (this.RTL) {
-      blockX = -blockX;
-    }
-    // Offset block until not clobbering another block and not in connection
-    // distance with neighbouring blocks.
-    do {
-      var collide = false;
-      var allBlocks = this.getAllBlocks();
-      for (var i = 0, otherBlock; otherBlock = allBlocks[i]; i++) {
-        var otherXY = otherBlock.getRelativeToSurfaceXY();
-        if (Math.abs(blockX - otherXY.x) <= 1 &&
-            Math.abs(blockY - otherXY.y) <= 1) {
-          collide = true;
-          break;
-        }
+  try {
+    var block = Blockly.Xml.domToBlock(xmlBlock, this);
+    // Move the duplicate to original position.
+    var blockX = parseInt(xmlBlock.getAttribute('x'), 10);
+    var blockY = parseInt(xmlBlock.getAttribute('y'), 10);
+    if (!isNaN(blockX) && !isNaN(blockY)) {
+      if (this.RTL) {
+        blockX = -blockX;
       }
-      if (!collide) {
-        // Check for blocks in snap range to any of its connections.
-        var connections = block.getConnections_(false);
-        for (var i = 0, connection; connection = connections[i]; i++) {
-          var neighbour = connection.closest(Blockly.SNAP_RADIUS,
-              new goog.math.Coordinate(blockX, blockY));
-          if (neighbour.connection) {
+      // Offset block until not clobbering another block and not in connection
+      // distance with neighbouring blocks.
+      do {
+        var collide = false;
+        var allBlocks = this.getAllBlocks();
+        for (var i = 0, otherBlock; otherBlock = allBlocks[i]; i++) {
+          var otherXY = otherBlock.getRelativeToSurfaceXY();
+          if (Math.abs(blockX - otherXY.x) <= 1 &&
+              Math.abs(blockY - otherXY.y) <= 1) {
             collide = true;
             break;
           }
         }
-      }
-      if (collide) {
-        if (this.RTL) {
-          blockX -= Blockly.SNAP_RADIUS;
-        } else {
-          blockX += Blockly.SNAP_RADIUS;
+        if (!collide) {
+          // Check for blocks in snap range to any of its connections.
+          var connections = block.getConnections_(false);
+          for (var i = 0, connection; connection = connections[i]; i++) {
+            var neighbour = connection.closest(Blockly.SNAP_RADIUS,
+                new goog.math.Coordinate(blockX, blockY));
+            if (neighbour.connection) {
+              collide = true;
+              break;
+            }
+          }
         }
-        blockY += Blockly.SNAP_RADIUS * 2;
-      }
-    } while (collide);
-    block.moveBy(blockX, blockY);
+        if (collide) {
+          if (this.RTL) {
+            blockX -= Blockly.SNAP_RADIUS;
+          } else {
+            blockX += Blockly.SNAP_RADIUS;
+          }
+          blockY += Blockly.SNAP_RADIUS * 2;
+        }
+      } while (collide);
+      block.moveBy(blockX, blockY);
+    }
+  } finally {
+    Blockly.Events.enable();
   }
-  Blockly.Events.enable();
   if (Blockly.Events.isEnabled() && !block.isShadow()) {
     Blockly.Events.fire(new Blockly.Events.Create(block));
   }
diff --git a/core/xml.js b/core/xml.js
index 70fd915a5..7f096956a 100644
--- a/core/xml.js
+++ b/core/xml.js
@@ -332,32 +332,35 @@ Blockly.Xml.domToBlock = function(xmlBlock, workspace) {
   }
   // Create top-level block.
   Blockly.Events.disable();
-  var topBlock = Blockly.Xml.domToBlockHeadless_(xmlBlock, workspace);
-  if (workspace.rendered) {
-    // Hide connections to speed up assembly.
-    topBlock.setConnectionsHidden(true);
-    // Generate list of all blocks.
-    var blocks = topBlock.getDescendants();
-    // Render each block.
-    for (var i = blocks.length - 1; i >= 0; i--) {
-      blocks[i].initSvg();
-    }
-    for (var i = blocks.length - 1; i >= 0; i--) {
-      blocks[i].render(false);
-    }
-    // Populating the connection database may be defered until after the blocks
-    // have renderend.
-    setTimeout(function() {
-      if (topBlock.workspace) {  // Check that the block hasn't been deleted.
-        topBlock.setConnectionsHidden(false);
+  try {
+    var topBlock = Blockly.Xml.domToBlockHeadless_(xmlBlock, workspace);
+    if (workspace.rendered) {
+      // Hide connections to speed up assembly.
+      topBlock.setConnectionsHidden(true);
+      // Generate list of all blocks.
+      var blocks = topBlock.getDescendants();
+      // Render each block.
+      for (var i = blocks.length - 1; i >= 0; i--) {
+        blocks[i].initSvg();
       }
-    }, 1);
-    topBlock.updateDisabled();
-    // Allow the scrollbars to resize and move based on the new contents.
-    // TODO(@picklesrus): #387. Remove when domToBlock avoids resizing.
-    Blockly.resizeSvgContents(workspace);
+      for (var i = blocks.length - 1; i >= 0; i--) {
+        blocks[i].render(false);
+      }
+      // Populating the connection database may be defered until after the
+      // blocks have rendered.
+      setTimeout(function() {
+        if (topBlock.workspace) {  // Check that the block hasn't been deleted.
+          topBlock.setConnectionsHidden(false);
+        }
+      }, 1);
+      topBlock.updateDisabled();
+      // Allow the scrollbars to resize and move based on the new contents.
+      // TODO(@picklesrus): #387. Remove when domToBlock avoids resizing.
+      Blockly.resizeSvgContents(workspace);
+    }
+  } finally {
+    Blockly.Events.enable();
   }
-  Blockly.Events.enable();
   if (Blockly.Events.isEnabled()) {
     Blockly.Events.fire(new Blockly.Events.Create(topBlock));
   }