Jeroen Corthout is the co-founder of Salesflare, a company that creates an artificial intelligence sales assistant. The document discusses lean sales techniques including leveraging one's existing network for warm leads, using tools like LinkedIn and advertising for lead generation, and qualifying leads quickly using available online data. It emphasizes following up with prospects in a proactive manner through automated suggestions, maintaining a 360 degree view of customers, and easy team collaboration on accounts. The goal is to close more deals with less effort through smart follow-up capabilities that integrate data from various business systems and synchronize activities.