Brian Halligan is the former CEO, co-founder and now executive chairperson of HubSpot who revolutionized marketing with the concept of "inbound marketing." In this podcast, he shares his journey of building HubSpot and the evolution of the inbound marketing methodology. He emphasizes the importance of international expansion and the challenges of scaling a company. Brian also discusses the concept of "grinding it out" and the need for continuous improvement. In addition, he talks about his new venture, Propeller, a fund that invests in companies working on climate and ocean-related solutions.