diff --git a/bin/smsd b/bin/smsd
new file mode 100755
index 0000000..37d4075
--- /dev/null
+++ b/bin/smsd
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+
+require 'smsd'
+
+SMSd::CLI.new(ARGV)
diff --git a/lib/smsd.rb b/lib/smsd.rb
index 96abdb7..0c57d07 100644
--- a/lib/smsd.rb
+++ b/lib/smsd.rb
@@ -1,5 +1,18 @@
-require "smsd/version"
+require 'i18n'
 
-module Smsd
-  # Your code goes here...
+require 'smsd/version'
+require 'smsd/cli'
+require 'smsd/cli/options'
+require 'smsd/answering_machine'
+require 'smsd/answering_machine/action'
+
+module SMSd
+  def self.init_i18n
+    I18n.load_path = Dir[File.join(File.dirname(__FILE__),
+                         '..', 'locale', '*.yml')]
+  end
+
+  def self.locale=(locale)
+    I18n.locale = locale
+  end
 end
diff --git a/lib/smsd/answering_machine.rb b/lib/smsd/answering_machine.rb
new file mode 100644
index 0000000..ef492ab
--- /dev/null
+++ b/lib/smsd/answering_machine.rb
@@ -0,0 +1,22 @@
+module SMSd
+  class AnsweringMachine
+    attr_accessor :actions, :default_action
+
+    def initialize(default_answer = nil, &block)
+      self.actions = []
+      self.default_action = Action.new(nil, default_answer, &block)
+    end
+
+    def add_action(regexp, answer = nil, &block)
+      self.actions << Action.new(regexp, answer, &block)
+    end
+
+    def execute(from, to, message)
+      actions.each do |action|
+        return action.answer(from, to, message) if message =~ action.regexp
+      end
+
+      default_action.answer(from, to, message)
+    end
+  end
+end
diff --git a/lib/smsd/answering_machine/action.rb b/lib/smsd/answering_machine/action.rb
new file mode 100644
index 0000000..77ea6c3
--- /dev/null
+++ b/lib/smsd/answering_machine/action.rb
@@ -0,0 +1,21 @@
+module SMSd
+  class AnsweringMachine
+    class Action
+      attr_accessor :regexp, :action
+
+      def initialize(regexp, answer = nil, &block)
+        self.regexp = regexp
+        self.action = (block_given? ? block : answer)
+      end
+
+      def answer(from, to, message)
+        case action
+        when String
+          action
+        when Proc
+          action.call(from, to, message)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/smsd/cli.rb b/lib/smsd/cli.rb
new file mode 100644
index 0000000..1c0a390
--- /dev/null
+++ b/lib/smsd/cli.rb
@@ -0,0 +1,25 @@
+module SMSd
+  class CLI
+    attr_accessor :machine, :options
+
+    def initialize(args)
+      self.options = Options.parse(args)
+
+      SMSd.init_i18n
+      SMSd.locale = options[:locale] || :fr
+
+      define_actions
+
+      puts machine.execute(ARGV[0], ARGV[1], ARGV[2])
+    end
+
+    def define_actions
+      self.machine = AnsweringMachine.new(I18n.t(:default_answer))
+
+      machine.add_action(/bonjour/i, 'Bonjour !!')
+      machine.add_action(/quoi/i) do |from, to, message|
+        I18n.t(:what, from: from, to: to, message: message)
+      end
+    end
+  end
+end
diff --git a/lib/smsd/cli/options.rb b/lib/smsd/cli/options.rb
new file mode 100644
index 0000000..1cbc447
--- /dev/null
+++ b/lib/smsd/cli/options.rb
@@ -0,0 +1,39 @@
+require 'optparse'
+
+module SMSd
+  class CLI
+    class Options
+      def self.parse(args)
+        options = {}
+
+        parser = ::OptionParser.new do |opts|
+          opts.banner = "Usage: smsd [options]"
+
+          opts.separator ""
+          opts.separator "Specific options:"
+
+          opts.on('-l', '--locale LOCALE',
+                  'Define the language of the script') do |locale|
+            options[:locale] = locale.to_sym
+          end
+
+          opts.separator ""
+          opts.separator "Common options:"
+
+          opts.on('-h', '--help', 'Show this message') do
+            puts opts
+            exit
+          end
+
+          opts.on_tail('--version', 'Show version') do
+            puts "#{opts.program_name} #{SMSd::VERSION}"
+            exit
+          end
+        end
+
+        parser.parse!(args)
+        options
+      end
+    end
+  end
+end
diff --git a/lib/smsd/version.rb b/lib/smsd/version.rb
index fcc01ac..45ca28a 100644
--- a/lib/smsd/version.rb
+++ b/lib/smsd/version.rb
@@ -1,3 +1,3 @@
-module Smsd
+module SMSd
   VERSION = "0.0.1"
 end
diff --git a/locale/en.yml b/locale/en.yml
new file mode 100644
index 0000000..0f31a25
--- /dev/null
+++ b/locale/en.yml
@@ -0,0 +1,3 @@
+en:
+  default_answer: "I didn't understand your message"
+  what: 'The phone number %{from} wrote "%{message} to %{to}'
diff --git a/locale/fr.yml b/locale/fr.yml
new file mode 100644
index 0000000..755b8d9
--- /dev/null
+++ b/locale/fr.yml
@@ -0,0 +1,3 @@
+fr:
+  default_answer: "Je n'ai pas compris votre message"
+  what: 'Le numéro %{from} a écrit "%{message}" au numéro %{to}'
diff --git a/smsd.gemspec b/smsd.gemspec
index 267423a..266372f 100644
--- a/smsd.gemspec
+++ b/smsd.gemspec
@@ -5,7 +5,7 @@ require 'smsd/version'
 
 Gem::Specification.new do |spec|
   spec.name          = "smsd"
-  spec.version       = Smsd::VERSION
+  spec.version       = SMSd::VERSION
   spec.authors       = ["Guillaume DOTT"]
   spec.email         = ["guillaume.dott@lafourmi-immo.com"]
   spec.description   = %q{TODO: Write a gem description}
@@ -18,6 +18,8 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ["lib"]
 
+  spec.add_dependency 'i18n'
+
   spec.add_development_dependency "bundler", "~> 1.3"
   spec.add_development_dependency "rake"
 end