diff --git a/README.md b/README.md
index bd35281..1467430 100644
--- a/README.md
+++ b/README.md
@@ -208,6 +208,8 @@ The `publish` method also accepts options that impact instantiation of the
   will be attempted before giving up. If the timeout is exceeded, an exception
   will raised to be handled by your application or `error_handler`. *(default:
   15)*
+* `:config` - A custom configuration object. Generally this option can be ignored.
+  *(default: `Circuitry.publisher_config`)*
 
 ```ruby
 obj = { foo: 'foo', bar: 'bar' }
@@ -258,6 +260,8 @@ The `subscribe` method also accepts options that impact instantiation of the
   short-polling. *(default: 10)*
 * `:batch_size` - The number of messages to retrieve in a single SQS request.
   *(default: 10)*
+* `:config` - A custom configuration object. Generally this option can be ignored.
+  *(default: `Circuitry.subscriber_config`)*
 
 ```ruby
 options = {
diff --git a/lib/circuitry/concerns/async.rb b/lib/circuitry/concerns/async.rb
index 373aa4b..07dbe06 100644
--- a/lib/circuitry/concerns/async.rb
+++ b/lib/circuitry/concerns/async.rb
@@ -17,10 +17,6 @@ module ClassMethods
         def async_strategies
           [:fork, :thread, :batch]
         end
-
-        def default_async_strategy
-          raise NotImplementedError, "#{name} must implement class method `default_async_strategy`"
-        end
       end
 
       def process_asynchronously(&block)
@@ -32,7 +28,7 @@ def process_asynchronously(&block)
       def async=(value)
         value = case value
                 when false, nil then false
-                when true then self.class.default_async_strategy
+                when true then config.async_strategy
                 when *self.class.async_strategies then value
                 else raise ArgumentError, async_value_error(value)
                 end
diff --git a/lib/circuitry/publisher.rb b/lib/circuitry/publisher.rb
index 87aa033..b8636bc 100644
--- a/lib/circuitry/publisher.rb
+++ b/lib/circuitry/publisher.rb
@@ -20,11 +20,12 @@ class Publisher
       ::Aws::SNS::Errors::InternalFailure
     ].freeze
 
-    attr_reader :timeout
+    attr_reader :config, :timeout
 
     def initialize(options = {})
       options = DEFAULT_OPTIONS.merge(options)
 
+      self.config = options[:config] || Circuitry.publisher_config
       self.async = options[:async]
       self.timeout = options[:timeout]
     end
@@ -43,10 +44,6 @@ def publish(topic_name, object)
       end
     end
 
-    def self.default_async_strategy
-      Circuitry.publisher_config.async_strategy
-    end
-
     protected
 
     def publish_message(topic_name, message)
@@ -68,13 +65,9 @@ def publish_message(topic_name, message)
       end
     end
 
-    def config
-      Circuitry.publisher_config
-    end
-
     private
 
-    attr_writer :timeout
+    attr_writer :config, :timeout
 
     def logger
       config.logger
diff --git a/lib/circuitry/subscriber.rb b/lib/circuitry/subscriber.rb
index 220ffd3..6941eae 100644
--- a/lib/circuitry/subscriber.rb
+++ b/lib/circuitry/subscriber.rb
@@ -12,7 +12,7 @@ class Subscriber
     include Concerns::Async
     include Services::SQS
 
-    attr_reader :queue, :timeout, :wait_time, :batch_size, :lock
+    attr_reader :config, :timeout, :wait_time, :batch_size, :lock
 
     DEFAULT_OPTIONS = {
       lock: true,
@@ -30,7 +30,7 @@ def initialize(options = {})
       options = DEFAULT_OPTIONS.merge(options)
 
       self.subscribed = false
-      self.queue = Queue.find(config.queue_name).url
+      self.config = options[:config] || Circuitry.subscriber_config
 
       %i[lock async timeout wait_time batch_size].each do |sym|
         send(:"#{sym}=", options[sym])
@@ -41,35 +41,33 @@ def initialize(options = {})
 
     def subscribe(&block)
       raise ArgumentError, 'block required' if block.nil?
+      raise SubscribeError, 'already subscribed' if subscribed?
       raise SubscribeError, 'AWS configuration is not set' unless can_subscribe?
 
-      logger.info("Subscribing to queue: #{queue}")
-
-      self.subscribed = true
+      subscribed!
       poll(&block)
-      self.subscribed = false
-
-      logger.info("Unsubscribed from queue: #{queue}")
     rescue *CONNECTION_ERRORS => e
       logger.error("Connection error to queue: #{queue}: #{e}")
       raise SubscribeError, e.message
+    ensure
+      unsubscribed!
     end
 
     def subscribed?
       subscribed
     end
 
-    def self.async_strategies
-      super - [:batch]
+    def queue
+      @queue ||= Queue.find(config.queue_name).url
     end
 
-    def self.default_async_strategy
-      Circuitry.subscriber_config.async_strategy
+    def self.async_strategies
+      super - [:batch]
     end
 
     protected
 
-    attr_writer :queue, :timeout, :wait_time, :batch_size
+    attr_writer :config, :timeout, :wait_time, :batch_size
     attr_accessor :subscribed
 
     def lock=(value)
@@ -83,10 +81,6 @@ def lock=(value)
       @lock = value
     end
 
-    def config
-      Circuitry.subscriber_config
-    end
-
     private
 
     def lock_value_error(value)
@@ -103,6 +97,16 @@ def trap_signals
       end
     end
 
+    def subscribed!
+      logger.info("Subscribing to queue: #{queue}") unless subscribed?
+      self.subscribed = true
+    end
+
+    def unsubscribed!
+      logger.info("Unsubscribed from queue: #{queue}") if subscribed?
+      self.subscribed = false
+    end
+
     def poll(&block)
       poller = Aws::SQS::QueuePoller.new(queue, client: sqs)
 
diff --git a/spec/circuitry/concerns/async_spec.rb b/spec/circuitry/concerns/async_spec.rb
index dc5c63b..b7dc16c 100644
--- a/spec/circuitry/concerns/async_spec.rb
+++ b/spec/circuitry/concerns/async_spec.rb
@@ -3,10 +3,6 @@
 async_class = Class.new do
   include Circuitry::Concerns::Async
 
-  def self.default_async_strategy
-    :thread
-  end
-
   def self.async_strategies
     [:fork, :thread, :batch]
   end
@@ -16,14 +12,6 @@ def config
   end
 end
 
-incomplete_async_class = Class.new do
-  include Circuitry::Concerns::Async
-
-  def config
-    Circuitry.subscriber_config
-  end
-end
-
 RSpec.describe Circuitry::Concerns::Async, type: :model do
   subject { async_class.new }
 
@@ -48,20 +36,8 @@ def config
     end
 
     describe 'with true' do
-      describe 'when the class has defined a default async strategy' do
-        it 'sets async to the default value' do
-          expect(subject.class).to receive(:default_async_strategy).at_least(:once).and_call_original
-          subject.async = true
-          expect(subject.async).to eq subject.class.default_async_strategy
-        end
-      end
-
-      describe 'when the class has not defined a default async strategy' do
-        subject { incomplete_async_class.new }
-
-        it 'raises an error' do
-          expect { subject.async = true }.to raise_error(NotImplementedError)
-        end
+      it 'sets async to the default value' do
+        expect { subject.async = true }.to change { subject.async }.to(subject.config.async_strategy)
       end
     end