diff --git a/lib/hostel/detectable.rb b/lib/hostel/detectable.rb
index 3565871..3c36eae 100644
--- a/lib/hostel/detectable.rb
+++ b/lib/hostel/detectable.rb
@@ -11,7 +11,9 @@ module Detectable
 
     def current_site
       @current_site ||= begin
-        if site = Hostel.find(request.params[:pinned])
+        if site = subdomain_override?(request)
+          site
+        elsif site = Hostel.find(request.params[:pinned])
           cookies[:pinned] = site.key
           Hostel::Detector.new(site.domain).site
         elsif request.headers['X-PROXIED-FOR']
@@ -21,5 +23,13 @@ def current_site
         end
       end
     end
+
+    private
+    def subdomain_override?(request)
+      ['cio', 'cco'].each do |sk|
+        return Hostel.find(sk) if request.subdomain.include?(sk)
+      end
+      nil
+    end
   end
 end
diff --git a/lib/hostel/domain_constraint.rb b/lib/hostel/domain_constraint.rb
index 5fdf362..20fb126 100644
--- a/lib/hostel/domain_constraint.rb
+++ b/lib/hostel/domain_constraint.rb
@@ -5,12 +5,26 @@ def initialize(*site_keys)
     end
 
     def matches?(request)
-      if request.headers['X-PROXIED-FOR']
-        current_site = Hostel::Detector.new(request.headers['X-PROXIED-FOR'], request.cookies['pinned']).site
+      current_site = if subdomain_override?(request)
+        subdomain_override(request)
+      elsif request.headers['X-PROXIED-FOR']
+        Hostel::Detector.new(request.headers['X-PROXIED-FOR'], request.cookies['pinned']).site
       else
-        current_site = Hostel::Detector.new(request.host_with_port, request.cookies['pinned']).site
+        Hostel::Detector.new(request.host_with_port, request.cookies['pinned']).site
       end
       @site_keys.include?(current_site.key)
     end
+
+    def subdomain_override?(request)
+      ['cio', 'cco'].each do |sk|
+        return Hostel.find(sk) if request.subdomain.include?(sk)
+      end
+      nil
+    end
+
+    # method delegation to express that this can also be used to retrive the value
+    def subdomain_override(request)
+      subdomain_override?(request)
+    end
   end
 end