diff --git a/bin/peck b/bin/peck
index fbf46f0..f758ebc 100755
--- a/bin/peck
+++ b/bin/peck
@@ -10,6 +10,7 @@ if options.first.has_key?('h') || options.first.has_key?('help')
   puts <<-EOF
 Usage: peck [options] [files]
 
+  -c, --concurrency        set the number of threads used to run the suite
   -e, --match-regexp       run tests that match a given regular expression
   -t, --match-text         run tests that match a given string
   -a, --recently-accessed  run tests that have been updated in the last 15 minutes
@@ -24,6 +25,10 @@ unless (%w(v version) & options.first.keys).empty?
   exit 1
 end
 
+if concurrency = options.first['c'] || options.first['concurrency']
+  Peck.concurrency = concurrency.to_i
+end
+
 if match_regexp = options.first['e'] || options.first['match-regexp']
   Peck.spec_selector = Regexp.new(match_regexp)
 end
diff --git a/lib/peck.rb b/lib/peck.rb
index 60bed1a..cd12021 100644
--- a/lib/peck.rb
+++ b/lib/peck.rb
@@ -88,7 +88,7 @@ def self.run_serial
   end
 
   def self.run_concurrent
-    Peck.log("Running specs concurrently")
+    Peck.log("Running specs concurrently (#{Peck.concurrency} threads)")
     current_spec = -1
     specs = all_specs
     threaded do |nr|