diff --git a/lib/channel.rb b/lib/channel.rb
new file mode 100644
index 00000000..1f6d4e51
--- /dev/null
+++ b/lib/channel.rb
@@ -0,0 +1,32 @@
+module SlackBot
+  class Channel < Recipient
+    PATH_URL = "channels.list?"
+    attr_reader :num_members, :name, :id
+
+    def initialize(num_members:, name:, id:)
+      @num_members = num_members
+      @name = name
+      @id = id
+    end
+
+    def self.list
+      response = get(PATH_URL)
+      check_response_code(response)
+
+      channels_array = response["channels"].map do |channel|
+        SlackBot::Channel.new(num_members: channel["num_members"], name: channel["name"], id: channel["id"])
+      end
+
+      return channels_array
+    end
+
+    def details
+      channel_details = {
+        num_members: @num_members,
+        name: @name,
+        id: @id,
+      }
+      return channel_details
+    end
+  end
+end
diff --git a/lib/recipient.rb b/lib/recipient.rb
new file mode 100644
index 00000000..bed56070
--- /dev/null
+++ b/lib/recipient.rb
@@ -0,0 +1,43 @@
+module SlackBot
+  class SlackApiError < StandardError; end
+
+  class Recipient
+    BASE_URL = "https://slack.com/api/"
+    TOKEN = ENV["TOKEN"]
+    def self.list
+      raise NotImplementedError
+    end
+
+    def details
+      raise NotImplementedError
+    end
+
+    def send_message(message)
+      body = {
+        text: message,
+        channel: id,
+        token: TOKEN,
+      }
+      response = HTTParty.post("#{BASE_URL}chat.postMessage", body: body, headers: { "Content-type" => "application/x-www-form-urlencoded" })
+      unless response.code == 200 && response.parsed_response["ok"]
+        raise SlackApiError, "Error when posting #{message} to #{id}, error: #{response.parsed_response["error"]}"
+      end
+
+      return true
+    end
+
+    def self.check_response_code(response)
+      unless response.code == 200 && response.parsed_response["ok"]
+        raise SlackApiError, "Error when posting #{message} to #{id}, error: #{response.parsed_response["error"]}"
+      end
+    end
+
+    private
+
+    def self.get(path_url)
+      query_parameters = { token: TOKEN }
+      response = HTTParty.get("#{BASE_URL}#{path_url}", query: query_parameters)
+      return response
+    end
+  end
+end
diff --git a/lib/slack.rb b/lib/slack.rb
index 960cf2f7..69aec403 100755
--- a/lib/slack.rb
+++ b/lib/slack.rb
@@ -1,11 +1,91 @@
 #!/usr/bin/env ruby
+require "table_print"
+require "HTTParty"
+require "dotenv"
+Dotenv.load
+
+require_relative "../lib/recipient.rb"
+require_relative "../lib/user.rb"
+require_relative "../lib/channel.rb"
+require_relative "../lib/workspace.rb"
+
+def get_user_options_input(options)
+  input = gets.chomp.to_s.strip
+  until options.include?(input)
+    puts "Please choose option from list"
+    input = gets.chomp.to_s.strip
+  end
+  puts "\n"
+  return input
+end
+
+def get_user_input(message_to_user)
+  input = gets.chomp.to_s.strip
+  until input.length > 0
+    puts message_to_user
+    input = gets.chomp.to_s.strip
+  end
+  puts "\n"
+  return input
+end
+
+def list_options
+  puts "\nPlease choose from these options:\n\n"
+  puts "Enter 'list users' to view all users"
+  puts "Enter 'list channels' to view all channels"
+  puts "Enter 'select user' to select a user"
+  puts "Enter 'select channel' to select a channel"
+  puts "Enter 'details' to display information about currently selected recipient"
+  puts "Enter 'send message' to send a message to selected recipient"
+  puts "Enter 'quit' to quit\n\n"
+end
 
 def main
   puts "Welcome to the Ada Slack CLI!"
+  workspace = SlackBot::Workspace.new
 
-  # TODO project
+  while true
+    list_options
+    options = ["list users", "list channels", "select user", "select channel", "details", "send message", "quit"]
+    choice = get_user_options_input(options)
+    case choice
+    when "list users"
+      tp workspace.list_users
+    when "list channels"
+      tp workspace.list_channels
+    when "select user"
+      puts "Please enter a user ID or user name:"
+      input = get_user_input("Please enter an ID or name")
+      selected = workspace.select_user(input)
+      puts "Sorry, no user with that information" if selected == nil
+    when "select channel"
+      puts "Please enter a channel name channel ID"
+      input = get_user_input("Please enter an ID or name")
+      selected = workspace.select_channel(input)
+      puts "Sorry, no channel with that information" if selected == nil
+    when "details"
+      if workspace.selected
+        tp [selected.details]
+      else
+        puts "Please select a user or channel first"
+      end
+    when "send message"
+      if !workspace.selected
+        puts "A recipient needs to be selected first"
+      else
+        puts "Enter the message you would like to send: "
+        message_to_send = get_user_input("Message must be at least one character")
+        workspace.send_message(message_to_send)
+        puts "Message sent!"
+      end
+    when "quit"
+      puts "Goodbye!"
+      exit
+    end
+    puts "\n\n"
+  end
 
   puts "Thank you for using the Ada Slack CLI"
 end
 
-main if __FILE__ == $PROGRAM_NAME
\ No newline at end of file
+main if __FILE__ == $PROGRAM_NAME
diff --git a/lib/slack_api_error.rb b/lib/slack_api_error.rb
new file mode 100644
index 00000000..e69de29b
diff --git a/lib/user.rb b/lib/user.rb
new file mode 100644
index 00000000..9266bd6c
--- /dev/null
+++ b/lib/user.rb
@@ -0,0 +1,34 @@
+require "pry"
+
+module SlackBot
+  class User < Recipient
+    PATH_URL = "users.list?"
+    attr_reader :real_name, :name, :id
+
+    def initialize(real_name:, name:, id:)
+      @real_name = real_name
+      @name = name
+      @id = id
+    end
+
+    def self.list
+      response = get(PATH_URL)
+      check_response_code(response)
+
+      users_array = response["members"].map do |user|
+        SlackBot::User.new(real_name: user["real_name"], name: user["name"], id: user["id"])
+      end
+
+      return users_array
+    end
+
+    def details
+      user_details = {
+        real_name: @real_name,
+        name: @name,
+        id: @id,
+      }
+      return user_details
+    end
+  end
+end
diff --git a/lib/workspace.rb b/lib/workspace.rb
new file mode 100644
index 00000000..06a8430c
--- /dev/null
+++ b/lib/workspace.rb
@@ -0,0 +1,45 @@
+module SlackBot
+  class Workspace
+    attr_reader :users, :channels, :selected
+
+    def initialize
+      @users = SlackBot::User.list
+      @channels = SlackBot::Channel.list
+      @selected = nil
+    end
+
+    def list_users
+      user_list = @users.map do |user|
+        user.details
+      end
+      return user_list
+    end
+
+    def list_channels
+      channel_list = @channels.map do |channel|
+        channel.details
+      end
+      return channel_list
+    end
+
+    def select_user(input)
+      found_user = @users.find do |user|
+        input == user.id || input == user.name
+      end
+      @selected = found_user
+    end
+
+    def select_channel(input)
+      found_channel = @channels.find do |channel|
+        input == channel.id || input == channel.name
+      end
+      @selected = found_channel
+    end
+
+    def send_message(message)
+      return false if !selected
+      selected.send_message(message)
+      return true
+    end
+  end
+end
diff --git a/specs/channel_spec.rb b/specs/channel_spec.rb
new file mode 100644
index 00000000..9646abea
--- /dev/null
+++ b/specs/channel_spec.rb
@@ -0,0 +1,47 @@
+require_relative "test_helper"
+
+describe "channel" do
+  describe "self.list" do
+    it "Returns an array of hashes" do
+      VCR.use_cassette("self.list") do
+        channel_list = SlackBot::Channel.list
+
+        expect(channel_list).must_be_kind_of Array
+        expect(channel_list.first).must_be_kind_of SlackBot::Channel
+        expect(channel_list.last).must_be_kind_of SlackBot::Channel
+      end
+    end
+    it "Returns a real_name" do
+        VCR.use_cassette("self.list") do
+            channel_list = SlackBot::Channel.list
+
+        expect(channel_list.first.num_members).must_equal 2
+        expect(channel_list.first.id).must_equal "CH2P99HT5"
+        expect(channel_list.first.name).must_equal "slack-api-project"
+        end
+    end
+  end
+  describe "send message" do
+    before do 
+      VCR.use_cassette("send message to channel") do
+        @channel_list = SlackBot::Channel.list
+      end
+    end
+      
+     it "returns true if given a valid message" do
+      VCR.use_cassette("send message with empty string to channel") do
+        message = "Hello!"
+        expect(@channel_list.first.send_message(message)).must_equal true
+      end
+    end
+
+    it "returns a slackapierror when given an empty string" do
+      VCR.use_cassette("send message with empty string to channel") do
+        message = ""
+        expect {
+        @channel_list.first.send_message(message)
+        }.must_raise SlackBot::SlackApiError
+      end
+    end
+  end
+end
diff --git a/specs/recipient_spec.rb b/specs/recipient_spec.rb
new file mode 100644
index 00000000..f917f426
--- /dev/null
+++ b/specs/recipient_spec.rb
@@ -0,0 +1,20 @@
+require_relative "test_helper"
+
+describe "Recipient" do
+  describe "self.list" do
+    it "Raises NotImplementedError if called directly on recipient" do
+      expect {
+        SlackBot::Recipient.list
+      }.must_raise NotImplementedError
+    end
+  end
+
+  describe "details" do
+    it "Raise NotImplementedError if called directory on recipient" do
+      recipient = SlackBot::Recipient.new
+      expect {
+        recipient.details
+      }.must_raise NotImplementedError
+    end
+  end
+end
diff --git a/specs/test_helper.rb b/specs/test_helper.rb
index 81ccd06b..24762ca6 100644
--- a/specs/test_helper.rb
+++ b/specs/test_helper.rb
@@ -1,15 +1,33 @@
-require 'simplecov'
+require "simplecov"
 SimpleCov.start
 
-require 'minitest'
-require 'minitest/autorun'
-require 'minitest/reporters'
-require 'minitest/skip_dsl'
-require 'vcr'
+require "minitest"
+require "minitest/autorun"
+require "minitest/reporters"
+require "minitest/skip_dsl"
+require "HTTParty"
+require "vcr"
+require "webmock/minitest"
+require "dotenv"
+require "pry"
+Dotenv.load
 
 Minitest::Reporters.use! Minitest::Reporters::SpecReporter.new
 
 VCR.configure do |config|
   config.cassette_library_dir = "specs/cassettes"
   config.hook_into :webmock
-end
\ No newline at end of file
+  config.default_cassette_options = {
+    :record => :new_episodes,
+    :match_requests_on => [:method, :uri, :body],
+  }
+
+  config.filter_sensitive_data("<SLACK_TOKEN>") do
+    ENV["TOKEN"]
+  end
+end
+
+require_relative "../lib/recipient.rb"
+require_relative "../lib/user.rb"
+require_relative "../lib/channel.rb"
+require_relative "../lib/workspace.rb"
diff --git a/specs/user_spec.rb b/specs/user_spec.rb
new file mode 100644
index 00000000..a06aa668
--- /dev/null
+++ b/specs/user_spec.rb
@@ -0,0 +1,59 @@
+require_relative "test_helper"
+require "pry"
+
+describe "user" do
+  describe "initialize" do
+    before do
+      @new_user = SlackBot::User.new(real_name: "Sarah", name: "Riyo", id: "USRJFDJFKD")
+    end
+
+    it "creates an instance of user" do
+      expect(@new_user).must_be_kind_of SlackBot::User
+    end
+  end
+  describe "self.list" do
+    it "Returns an array of hashes" do
+      VCR.use_cassette("self.list") do
+        user_list = SlackBot::User.list
+
+        expect(user_list).must_be_kind_of Array
+        expect(user_list.first).must_be_kind_of SlackBot::User
+        expect(user_list.last).must_be_kind_of SlackBot::User
+      end
+    end
+    it "Returns users real_name, id and name" do
+      VCR.use_cassette("self.list") do
+        user_list = SlackBot::User.list
+
+        expect(user_list.first.real_name).must_equal "Slackbot"
+        expect(user_list.first.id).must_equal "USLACKBOT"
+        expect(user_list.first.name).must_equal "slackbot"
+      end
+    end
+
+  end
+  describe "send message" do
+    before do
+      VCR.use_cassette("send message") do
+        @user_list = SlackBot::User.list
+      end
+    end
+      
+     
+    it "returns true if given a valid message" do
+      VCR.use_cassette("send working message") do
+        message = "Hello!"
+        expect(@user_list.first.send_message(message)).must_equal true
+      end
+    end
+
+    it "returns a slackapierror when given an empty string" do
+      VCR.use_cassette("send message with empty string") do
+        message = ""
+        expect {
+        @user_list.first.send_message(message)
+        }.must_raise SlackBot::SlackApiError
+      end
+    end
+  end
+end
diff --git a/specs/workspace_spec.rb b/specs/workspace_spec.rb
new file mode 100644
index 00000000..746e4337
--- /dev/null
+++ b/specs/workspace_spec.rb
@@ -0,0 +1,120 @@
+require_relative "test_helper"
+
+describe "Workspace" do
+  describe "Initialize" do
+    before do
+      VCR.use_cassette("initialize") do
+        @workspace = SlackBot::Workspace.new
+      end
+    end
+    it "Creates a workspace object" do
+      expect(@workspace).must_be_kind_of SlackBot::Workspace
+    end
+
+    it "Initializes with selected equal to nil" do
+      assert_nil @workspace.selected
+    end
+    it "Creates a list of users" do
+      expect(@workspace.users).must_be_kind_of Array
+      expect(@workspace.users.first).must_be_kind_of SlackBot::User
+      expect(@workspace.users.first.real_name).must_equal "Slackbot"
+      expect(@workspace.users.first.name).must_equal "slackbot"
+      expect(@workspace.users.first.id).must_equal "USLACKBOT"
+    end
+  end
+  describe "list" do
+    before do
+      VCR.use_cassette("list") do
+        @workspace = SlackBot::Workspace.new
+      end
+    end
+    it "returns an array of hashes for list_users" do
+      users = @workspace.list_users
+      expect(users).must_be_kind_of Array
+      expect(users.first).must_be_kind_of Hash
+      expect(users.first[:name]).must_equal "slackbot"
+      expect(users.first[:id]).must_equal "USLACKBOT"
+      expect(users.first[:real_name]).must_equal "Slackbot"
+    end
+    it "returns an array of hashes for list_channel" do
+      channels = @workspace.list_channels
+      expect(channels).must_be_kind_of Array
+      expect(channels.first).must_be_kind_of Hash
+      expect(channels.first[:name]).must_equal "slack-api-project"
+      expect(channels.first[:id]).must_equal "CH2P99HT5"
+      expect(channels.first[:num_members]).must_equal 2
+    end
+  end
+  describe "select" do
+    before do
+      VCR.use_cassette("select") do
+        @workspace = SlackBot::Workspace.new
+      end
+    end
+    it "returns nil if no user found with id given" do
+      selected = @workspace.select_user("USLACKNOT")
+      assert_nil selected
+    end
+    it "returns nil if no user found with name given" do
+      selected = @workspace.select_user("Devin")
+      assert_nil selected
+    end
+    it "returns a User object if given a valid user id" do
+      selected = @workspace.select_user("USLACKBOT")
+      expect(selected).must_be_kind_of SlackBot::User
+      expect(selected.name).must_equal "slackbot"
+    end
+    it "returns a User object if given a valid user name" do
+      selected = @workspace.select_user("slackbot")
+      expect(selected).must_be_kind_of SlackBot::User
+      expect(selected.id).must_equal "USLACKBOT"
+    end
+
+    it "returns nil if no channel found with id given" do
+      selected = @workspace.select_channel("CH2P99HT6")
+      assert_nil selected
+    end
+    it "returns nil if no channel found with name given" do
+      selected = @workspace.select_channel("slack-bpi-project")
+      assert_nil selected
+    end
+    it "returns a Channel object if given a valid user id" do
+      selected = @workspace.select_channel("CH2SL5C3C")
+      expect(selected).must_be_kind_of SlackBot::Channel
+      expect(selected.name).must_equal "everyone"
+    end
+    it "returns a Channel object if given a valid name" do
+      selected = @workspace.select_channel("random")
+      expect(selected).must_be_kind_of SlackBot::Channel
+      expect(selected.id).must_equal "CH2SL5DEW"
+    end
+  end
+  describe "send message" do
+    before do
+      VCR.use_cassette("select") do
+        @workspace = SlackBot::Workspace.new
+      end
+    end
+
+    it "returns false if no user or channel is selected" do
+      expect(@workspace.send_message("Hi")).must_equal false
+    end
+
+    it "returns a slackapierror when given an empty message" do
+      VCR.use_cassette("send message with empty string") do
+        message = ""
+        expect {
+          @workspace.users.first.send_message(message)
+        }.must_raise SlackBot::SlackApiError
+      end
+    end
+
+    it "returns true if given a valid message and valid user/channel selected" do
+      VCR.use_cassette("send message with empty string") do
+        message = "Hello!"
+        @workspace.select_user(@workspace.users.first.id)
+        expect(@workspace.send_message(message)).must_equal true
+      end
+    end
+  end
+end