diff --git a/API.md b/API.md
index 78b3d6d..ebec9d2 100644
--- a/API.md
+++ b/API.md
@@ -226,6 +226,46 @@ $ curl -X DELETE --url vmpooler.company.com/api/v1/vm/fq6qlpjlsskycq6
 }
 ```
 
+#### Adding additional disk(s)
+
+##### POST /vm/<hostname>/disk/<size>
+
+Add an additional disk to a running VM.
+
+````
+$ curl -X POST -H X-AUTH-TOKEN:a9znth9dn01t416hrguu56ze37t790bl --url vmpooler.company.com/api/v1/vm/fq6qlpjlsskycq6/disk/8
+````
+````json
+{
+  "ok": true,
+  "fq6qlpjlsskycq6": {
+    "disk": "+8gb"
+  }
+}
+````
+
+Provisioning and attaching disks can take a moment, but once the task completes it will be reflected in a `GET /vm/<hostname>` query:
+
+````
+$ curl --url vmpooler.company.com/api/v1/vm/fq6qlpjlsskycq6
+````
+````json
+{
+  "ok": true,
+  "fq6qlpjlsskycq6": {
+    "template": "debian-7-x86_64",
+    "lifetime": 2,
+    "running": 0.08,
+    "state": "running",
+    "disk": [
+      "+8gb"
+    ],
+    "domain": "delivery.puppetlabs.net"
+  }
+}
+
+````
+
 #### VM snapshots
 
 ##### POST /vm/&lt;hostname&gt;/snapshot
diff --git a/lib/vmpooler/api/reroute.rb b/lib/vmpooler/api/reroute.rb
index 4f574a3..ea62ad1 100644
--- a/lib/vmpooler/api/reroute.rb
+++ b/lib/vmpooler/api/reroute.rb
@@ -62,6 +62,10 @@ module Vmpooler
     post '/vm/:hostname/snapshot/:snapshot/?' do
       call env.merge("PATH_INFO" => "/api/v#{api_version}/vm/#{params[:hostname]}/snapshot/#{params[:snapshot]}")
     end
+
+    put '/vm/:hostname/disk/:size/?' do
+      call env.merge("PATH_INFO" => "/api/v#{api_version}/vm/#{params[:hostname]}/disk/#{params[:size]}")
+    end
   end
   end
 end
diff --git a/lib/vmpooler/api/v1.rb b/lib/vmpooler/api/v1.rb
index a042351..1046593 100644
--- a/lib/vmpooler/api/v1.rb
+++ b/lib/vmpooler/api/v1.rb
@@ -455,6 +455,10 @@ module Vmpooler
           end
         end
 
+        if rdata['disk']
+          result[params[:hostname]]['disk'] = rdata['disk'].split(':')
+        end
+
         if config['domain']
           result[params[:hostname]]['domain'] = config['domain']
         end
@@ -552,6 +556,29 @@ module Vmpooler
       JSON.pretty_generate(result)
     end
 
+    post "#{api_prefix}/vm/:hostname/disk/:size/?" do
+      content_type :json
+
+      need_token! if Vmpooler::API.settings.config[:auth]
+
+      status 404
+      result = { 'ok' => false }
+
+      params[:hostname] = hostname_shorten(params[:hostname], config['domain'])
+
+      if ((params[:size].to_i > 0 )and (backend.exists('vmpooler__vm__' + params[:hostname])))
+        result[params[:hostname]] = {}
+        result[params[:hostname]]['disk'] = "+#{params[:size]}gb"
+
+        backend.sadd('vmpooler__tasks__disk', params[:hostname] + ':' + params[:size])
+
+        status 202
+        result['ok'] = true
+      end
+
+      JSON.pretty_generate(result)
+    end
+
     post "#{api_prefix}/vm/:hostname/snapshot/?" do
       content_type :json
 
diff --git a/lib/vmpooler/pool_manager.rb b/lib/vmpooler/pool_manager.rb
index eb9504f..065ec34 100644
--- a/lib/vmpooler/pool_manager.rb
+++ b/lib/vmpooler/pool_manager.rb
@@ -299,6 +299,47 @@ module Vmpooler
       end
     end
 
+    def create_vm_disk(vm, disk_size)
+      Thread.new do
+        _create_vm_disk(vm, disk_size)
+      end
+    end
+
+    def _create_vm_disk(vm, disk_size)
+      host = $vsphere['disk_manager'].find_vm(vm) ||
+             $vsphere['disk_manager'].find_vm_heavy(vm)[vm]
+
+      if (host) && ((! disk_size.nil?) && (! disk_size.empty?) && (disk_size.to_i > 0))
+        $logger.log('s', "[ ] [disk_manager] '#{vm}' is attaching a #{disk_size}gb disk")
+
+        start = Time.now
+
+        template = $redis.hget('vmpooler__vm__' + vm, 'template')
+        datastore = nil
+
+        $config[:pools].each do |pool|
+          if pool['name'] == template
+            datastore = pool['datastore']
+          end
+        end
+
+        if ((! datastore.nil?) && (! datastore.empty?))
+          $vsphere['disk_manager'].add_disk(host, disk_size, datastore)
+
+          rdisks = $redis.hget('vmpooler__vm__' + vm, 'disk')
+          disks = rdisks ? rdisks.split(':') : []
+          disks.push("+#{disk_size}gb")
+          $redis.hset('vmpooler__vm__' + vm, 'disk', disks.join(':'))
+
+          finish = '%.2f' % (Time.now - start)
+
+          $logger.log('s', "[+] [disk_manager] '#{vm}' attached #{disk_size}gb disk in #{finish} seconds")
+        else
+          $logger.log('s', "[+] [disk_manager] '#{vm}' failed to attach disk")
+        end
+      end
+    end
+
     def create_vm_snapshot(vm, snapshot_name)
       Thread.new do
         _create_vm_snapshot(vm, snapshot_name)
@@ -309,7 +350,7 @@ module Vmpooler
       host = $vsphere['snapshot_manager'].find_vm(vm) ||
              $vsphere['snapshot_manager'].find_vm_heavy(vm)[vm]
 
-      if (host) && ((! snapshot_name.nil?) || (! snapshot_name.empty?))
+      if (host) && ((! snapshot_name.nil?) && (! snapshot_name.empty?))
         $logger.log('s', "[ ] [snapshot_manager] '#{vm}' is being snapshotted")
 
         start = Time.now
@@ -356,6 +397,32 @@ module Vmpooler
       end
     end
 
+    def check_disk_queue
+      $logger.log('d', "[*] [disk_manager] starting worker thread")
+
+      $vsphere['disk_manager'] ||= Vmpooler::VsphereHelper.new
+
+      $threads['disk_manager'] = Thread.new do
+        loop do
+          _check_disk_queue
+          sleep(5)
+        end
+      end
+    end
+
+    def _check_disk_queue
+      vm = $redis.spop('vmpooler__tasks__disk')
+
+      unless vm.nil?
+        begin
+          vm_name, disk_size = vm.split(':')
+          create_vm_disk(vm_name, disk_size)
+        rescue
+          $logger.log('s', "[!] [disk_manager] disk creation appears to have failed")
+        end
+      end
+    end
+
     def check_snapshot_queue
       $logger.log('d', "[*] [snapshot_manager] starting worker thread")
 
@@ -544,6 +611,13 @@ module Vmpooler
       $redis.set('vmpooler__tasks__clone', 0)
 
       loop do
+        if ! $threads['disk_manager']
+          check_disk_queue
+        elsif ! $threads['disk_manager'].alive?
+          $logger.log('d', "[!] [disk_manager] worker thread died, restarting")
+          check_disk_queue
+        end
+
         if ! $threads['snapshot_manager']
           check_snapshot_queue
         elsif ! $threads['snapshot_manager'].alive?