This document discusses 4 free tools to help develop an impactful and relevant keyword list: SEMRush, Alexa, Google Adwords URL search, and Google Adwords. It provides details on how each tool can be used, such as using SEMRush to see top keywords a domain ranks for and Alexa to see keywords driving traffic to a site. The document recommends using these tools to build a comprehensive keyword list with low competition and back it up with data. It concludes by offering keyword development services from Marketing Works.