diff --git a/config/config.go b/config/config.go
index 811b77ec7ea9..901b0fc39777 100644
--- a/config/config.go
+++ b/config/config.go
@@ -84,8 +84,9 @@ type Resource struct {
 // ResourceLifecycle is used to store the lifecycle tuning parameters
 // to allow customized behavior
 type ResourceLifecycle struct {
-	CreateBeforeDestroy bool `mapstructure:"create_before_destroy"`
-	PreventDestroy      bool `mapstructure:"prevent_destroy"`
+	CreateBeforeDestroy bool     `mapstructure:"create_before_destroy"`
+	PreventDestroy      bool     `mapstructure:"prevent_destroy"`
+	IgnoreChanges       []string `mapstructure:"ignore_changes"`
 }
 
 // Provisioner is a configured provisioner step on a resource.
diff --git a/config/loader_test.go b/config/loader_test.go
index d239bd0b9ad3..eaf4f10aaa8b 100644
--- a/config/loader_test.go
+++ b/config/loader_test.go
@@ -440,6 +440,54 @@ func TestLoadFile_createBeforeDestroy(t *testing.T) {
 	}
 }
 
+func TestLoadFile_ignoreChanges(t *testing.T) {
+	c, err := LoadFile(filepath.Join(fixtureDir, "ignore-changes.tf"))
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if c == nil {
+		t.Fatal("config should not be nil")
+	}
+
+	actual := resourcesStr(c.Resources)
+	print(actual)
+	if actual != strings.TrimSpace(ignoreChangesResourcesStr) {
+		t.Fatalf("bad:\n%s", actual)
+	}
+
+	// Check for the flag value
+	r := c.Resources[0]
+	if r.Name != "web" && r.Type != "aws_instance" {
+		t.Fatalf("Bad: %#v", r)
+	}
+
+	// Should populate ignore changes
+	if len(r.Lifecycle.IgnoreChanges) == 0 {
+		t.Fatalf("Bad: %#v", r)
+	}
+
+	r = c.Resources[1]
+	if r.Name != "bar" && r.Type != "aws_instance" {
+		t.Fatalf("Bad: %#v", r)
+	}
+
+	// Should not populate ignore changes
+	if len(r.Lifecycle.IgnoreChanges) > 0 {
+		t.Fatalf("Bad: %#v", r)
+	}
+
+	r = c.Resources[2]
+	if r.Name != "baz" && r.Type != "aws_instance" {
+		t.Fatalf("Bad: %#v", r)
+	}
+
+	// Should not populate ignore changes
+	if len(r.Lifecycle.IgnoreChanges) > 0 {
+		t.Fatalf("Bad: %#v", r)
+	}
+}
+
 func TestLoad_preventDestroyString(t *testing.T) {
 	c, err := LoadFile(filepath.Join(fixtureDir, "prevent-destroy-string.tf"))
 	if err != nil {
@@ -676,3 +724,12 @@ aws_instance[bar] (x1)
 aws_instance[web] (x1)
   ami
 `
+
+const ignoreChangesResourcesStr = `
+aws_instance[bar] (x1)
+  ami
+aws_instance[baz] (x1)
+  ami
+aws_instance[web] (x1)
+  ami
+`
diff --git a/config/test-fixtures/ignore-changes.tf b/config/test-fixtures/ignore-changes.tf
new file mode 100644
index 000000000000..765a057983d2
--- /dev/null
+++ b/config/test-fixtures/ignore-changes.tf
@@ -0,0 +1,17 @@
+resource "aws_instance" "web" {
+    ami = "foo"
+    lifecycle {
+        ignore_changes = ["ami"]
+    }
+}
+
+resource "aws_instance" "bar" {
+    ami = "foo"
+    lifecycle {
+        ignore_changes = []
+    }
+}
+
+resource "aws_instance" "baz" {
+  ami = "foo"
+}
diff --git a/terraform/eval_ignore_changes.go b/terraform/eval_ignore_changes.go
new file mode 100644
index 000000000000..cad8e07b6153
--- /dev/null
+++ b/terraform/eval_ignore_changes.go
@@ -0,0 +1,33 @@
+package terraform
+import (
+	"github.com/hashicorp/terraform/config"
+	"strings"
+)
+
+// EvalIgnoreChanges is an EvalNode implementation that removes diff
+// attributes if their name matches names provided by the resource's
+// IgnoreChanges lifecycle.
+type EvalIgnoreChanges struct {
+	Resource *config.Resource
+	Diff **InstanceDiff
+}
+
+func (n *EvalIgnoreChanges) Eval(ctx EvalContext) (interface{}, error) {
+	if n.Diff == nil || *n.Diff == nil || n.Resource == nil || n.Resource.Id() == "" {
+		return nil, nil
+	}
+
+	diff := *n.Diff
+	ignoreChanges := n.Resource.Lifecycle.IgnoreChanges
+
+	for _, ignoredName := range	ignoreChanges {
+		for name := range diff.Attributes {
+			if strings.HasPrefix(name, ignoredName) {
+				delete(diff.Attributes, name)
+				diff.Attributes[name].GoString()
+			}
+		}
+	}
+
+	return nil, nil
+}
diff --git a/terraform/transform_resource.go b/terraform/transform_resource.go
index 0b56721b07a7..99efc1ad7244 100644
--- a/terraform/transform_resource.go
+++ b/terraform/transform_resource.go
@@ -318,6 +318,10 @@ func (n *graphNodeExpandedResource) EvalTree() EvalNode {
 					Resource: n.Resource,
 					Diff:     &diff,
 				},
+				&EvalIgnoreChanges{
+					Resource: n.Resource,
+					Diff: &diff,
+				},
 				&EvalWriteState{
 					Name:         n.stateId(),
 					ResourceType: n.Resource.Type,
diff --git a/website/source/docs/configuration/resources.html.md b/website/source/docs/configuration/resources.html.md
index f099c5f252e3..d5e087fec413 100644
--- a/website/source/docs/configuration/resources.html.md
+++ b/website/source/docs/configuration/resources.html.md
@@ -68,11 +68,20 @@ The `lifecycle` block allows the following keys to be set:
       destruction of a given resource. When this is set to `true`, any plan
       that includes a destroy of this resource will return an error message.
 
+  * `ignore_changes` (list of strings) - Customizes how diffs are evaluated for
+      resources, allowing individual attributes to be ignored through changes.
+      As an example, this can be used to ignore dynamic changes to the
+      resource from external resources. Other meta-parameters cannot be ignored.
+
 ~> **NOTE on create\_before\_destroy and dependencies:** Resources that utilize
 the `create_before_destroy` key can only depend on other resources that also
 include `create_before_destroy`. Referencing a resource that does not include
 `create_before_destroy` will result in a dependency graph cycle. 
 
+~> **NOTE on ignore\_changes:** Ignored attribute names can be matched by their
+name, not state ID. For example, if an `aws_route_table` has two routes defined
+and the `ignore_changes` list contains "route", both routes will be ignored.
+
 -------------
 
 Within a resource, you can optionally have a **connection block**.
@@ -191,6 +200,8 @@ where `LIFECYCLE` is:
 ```
 lifecycle {
     [create_before_destroy = true|false]
+    [prevent_destroy = true|false]
+    [ignore_changes = [ATTRIBUTE NAME, ...]]
 }
 ```