diff --git a/README.md b/README.md
index fc130e2..877cb4e 100644
--- a/README.md
+++ b/README.md
@@ -80,7 +80,10 @@ Accepts two arguments: an `options` object, and an optional `callback`. The `opt
 object can specify a number of optional arguments, including:
 
 * `name`: the name of the file system, defaults to `'"local'`
-* `flags`: one or more flags to use when creating/opening the file system. Use `'FORMAT'` to force Filer to format (i.e., erase) the file system
+* `flags`: an Array of one or more flags to use when creating/opening the file system:
+  *`'FORMAT'` to force Filer to format (i.e., erase) the file system
+  *`'NOCTIME'` to force Filer to not update `ctime` on nodes when metadata changes (i.e., for better performance)
+  *`'NOMTIME'` to force Filer to not update `mtime` on nodes when data changes (i.e., for better performance)
 * `provider`: an explicit storage provider to use for the file system's database context provider. See the section on [Storage Providers](#providers).
 
 The `callback` function indicates when the file system is ready for use. Depending on the storage provider used, this might
@@ -98,7 +101,7 @@ function fsReady(err, fs) {
 
 fs = new Filer.FileSystem({
   name: "my-filesystem",
-  flags: 'FORMAT',
+  flags: [ 'FORMAT' ],
   provider: new Filer.FileSystem.providers.Memory()
 }, fsReady);
 ```
diff --git a/src/constants.js b/src/constants.js
index 56a510a..660810f 100644
--- a/src/constants.js
+++ b/src/constants.js
@@ -33,8 +33,12 @@ define(function(require) {
 
     ROOT_DIRECTORY_NAME: '/', // basename(normalize(path))
 
+    // FS Mount Flags
     FS_FORMAT: 'FORMAT',
+    FS_NOCTIME: 'NOCTIME',
+    FS_NOMTIME: 'NOMTIME',
 
+    // FS File Open Flags
     O_READ: O_READ,
     O_WRITE: O_WRITE,
     O_CREATE: O_CREATE,
@@ -58,9 +62,6 @@ define(function(require) {
     XATTR_CREATE: XATTR_CREATE,
     XATTR_REPLACE: XATTR_REPLACE,
 
-    NOCTIME: 'NOCTIME',
-    NOMTIME: 'NOMTIME',
-
     FS_READY: 'READY',
     FS_PENDING: 'PENDING',
     FS_ERROR: 'ERROR',
diff --git a/src/fs.js b/src/fs.js
index b16376a..b5662eb 100644
--- a/src/fs.js
+++ b/src/fs.js
@@ -52,8 +52,8 @@ define(function(require) {
   var O_FLAGS = require('src/constants').O_FLAGS;
   var XATTR_CREATE = require('src/constants').XATTR_CREATE;
   var XATTR_REPLACE = require('src/constants').XATTR_REPLACE;
-  var NOMTIME = require('src/constants').NOMTIME;
-  var NOCTIME = require('src/constants').NOCTIME;
+  var FS_NOMTIME = require('src/constants').FS_NOMTIME;
+  var FS_NOCTIME = require('src/constants').FS_NOCTIME;
 
   var providers = require('src/providers/providers');
   var adapters = require('src/adapters/adapters');
@@ -138,10 +138,10 @@ define(function(require) {
   function update_node_times(context, path, node, times, callback) {
     // Honour mount flags for how we update times
     var flags = context.flags;
-    if(_(flags).contains(NOCTIME)) {
+    if(_(flags).contains(FS_NOCTIME)) {
       delete times.ctime;
     }
-    if(_(flags).contains(NOMTIME)) {
+    if(_(flags).contains(FS_NOMTIME)) {
       delete times.mtime;
     }