diff --git a/app/controllers/checkouts_controller.rb b/app/controllers/checkouts_controller.rb
index c6a5f554..923fde83 100644
--- a/app/controllers/checkouts_controller.rb
+++ b/app/controllers/checkouts_controller.rb
@@ -160,8 +160,6 @@ def uncheckin
         format.html { redirect_to tool_path(checkout.tool), notice: "Error" }
       end
     end
-
-    
   end
 
 
@@ -205,5 +203,6 @@ def checkin_bak
       end
     end
   end
+
 end
 
diff --git a/app/models/checkout.rb b/app/models/checkout.rb
index d3593823..96c2b6f1 100644
--- a/app/models/checkout.rb
+++ b/app/models/checkout.rb
@@ -22,6 +22,8 @@
 #
 
 class Checkout < ActiveRecord::Base
+  include Messenger
+
   # For lookups
   def card_number=( card_number )
     @card_number = card_number
@@ -35,6 +37,7 @@ def card_number
   validates_associated :tool, :organization, :participant
 
   before_save :checked_out_at, :presence => true
+  after_update :notify
 
   belongs_to :participant, :touch => true
   belongs_to :organization, :touch => true
@@ -44,4 +47,21 @@ def card_number
   scope :old, -> { where('checked_in_at IS NOT NULL') }
   scope :current, -> { where('checked_in_at IS NULL') }
 
-end
+  private
+
+  def notify
+    if (self.checked_in_at != nil)
+      toolCategory = self.tool.tool_type
+      waitlist = ToolWaitlist.for_tool_type(toolCategory.id).by_wait_start_time
+      if (waitlist.count != 0)
+        nextPerson = waitlist.first.participant
+        unless (nextPerson.phone_number.blank?)
+          number = nextPerson.phone_number
+          content = "#{toolCategory.name} is now available at the trailer. Please come pick it up within 5 minutes!"
+          send_sms(number, content)
+        end
+      end
+    end
+  end
+
+end
\ No newline at end of file
diff --git a/config/application.rb b/config/application.rb
index 6ca421a0..37c32fbd 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -26,8 +26,9 @@ class Application < Rails::Application
 
     config.autoload_paths += %W(#{config.root}/lib)
 
-    config.active_job.queue_adapter = :delayed_job
 
+    config.active_job.queue_adapter = :delayed_job
+    
     WillPaginate::ViewHelpers.pagination_options[:inner_window] = 1
     WillPaginate::ViewHelpers.pagination_options[:outer_window] = 0
   end
diff --git a/lib/messenger.rb b/lib/messenger.rb
index 3cc461f3..11de1700 100644
--- a/lib/messenger.rb
+++ b/lib/messenger.rb
@@ -1,3 +1,5 @@
+USER_UNSUBSCRIBED_FROM_TWILIO_ERROR_CODE = 21610
+
 module Messenger
 
   def send_sms(number, content)
@@ -6,17 +8,24 @@ def send_sms(number, content)
 
     @client = Twilio::REST::Client.new sid, auth
 
-    from = "+14123854063 "
-
-    message = @client.account.messages.create(
-             :from => from,
-             :to => '+1'+number,
-             :body => content
-    )
-  end
+    from = "+14123854063"
 
-  def receive_sms
+    # The following try-rescue block is needed in case user unsubscribe
+    # if the user ubsubscribe and we attempt to message them
+    # the api will report an error
 
+    begin
+      message = @client.account.messages.create(
+          :from => from,
+          :to => '+1'+number,
+          :body => content
+      )
+    rescue Twilio::REST::RequestError => e
+      case e.code
+        when USER_UNSUBSCRIBED_FROM_TWILIO_ERROR_CODE
+          puts e.message
+      end
+    end
   end
-
+  
 end
\ No newline at end of file