diff --git a/README.md b/README.md
index 5018d52..c068ec9 100644
--- a/README.md
+++ b/README.md
@@ -29,6 +29,9 @@ my_calendar_name:
         operator: matches # match against regex pattern
         val: # array of values also supported
           - '/Team A/i'
+      - field: blocking # blocking (TRANSP) field supported
+        operator: equals
+        val: true # true will filter out non-blocking events
    alarms: # (optional) create/clear alarms for filtered events
      clear_existing: true # (optional) if true, existing alarms will be removed, default: false
      triggers: # (optional) triggers for new alarms. Description will be the alarm summary, action is 'DISPLAY'
diff --git a/config.yml.example b/config.yml.example
index 5c3c413..bee591a 100644
--- a/config.yml.example
+++ b/config.yml.example
@@ -5,6 +5,9 @@ rota:
     - field: start_time
       operator: equals
       val: '09:00'
+    - field: blocking
+      operator: equals
+      val: true
   alarms:
     clear_existing: true
     triggers:
diff --git a/lib/ical_filter_proxy/filterable_event_adapter.rb b/lib/ical_filter_proxy/filterable_event_adapter.rb
index a4c9a09..74e0dfc 100644
--- a/lib/ical_filter_proxy/filterable_event_adapter.rb
+++ b/lib/ical_filter_proxy/filterable_event_adapter.rb
@@ -44,6 +44,11 @@ def end_components
       @end_components ||= DateComponents.new(dtend, options[:timezone])
     end
 
+    # extract and rename TRANSP field to something more obvious
+    def blocking
+      raw_event.transp == 'OPAQUE' || raw_event.transp.nil?
+    end
+
     def method_missing(method_sym, *args, &block)
       if method_sym.to_s =~ /(start|end)\_(\w+)/
         components = self.send("#{$1}_components")
diff --git a/spec/filterable_event_adapter_spec.rb b/spec/filterable_event_adapter_spec.rb
index 6f782ea..39c7514 100644
--- a/spec/filterable_event_adapter_spec.rb
+++ b/spec/filterable_event_adapter_spec.rb
@@ -87,4 +87,24 @@
       expect(adapter.end_date).to eq('2017-06-30')
     end
   end
+
+  describe '#blocking' do
+    it 'returns true if transp is OPAQUE' do
+      test_event.transp = 'OPAQUE'
+      adapter = described_class.new(test_event)
+      expect(adapter.blocking).to be true
+    end
+
+    it 'returns false if transp is TRANSPARENT' do
+      test_event.transp = 'TRANSPARENT'
+      adapter = described_class.new(test_event)
+      expect(adapter.blocking).to be false
+    end
+
+    it 'returns true if transp is nil (default)' do
+      test_event.transp = nil
+      adapter = described_class.new(test_event)
+      expect(adapter.blocking).to be true
+    end
+  end
 end