Two founders I know built a multimillion-dollar agency together. From the outside, it looked like a success story. Inside, one was waking up every morning to a backlog of Slack messages from the other, who started each day trying to contain small fires before his partner even rolled out of bed. Their disagreements weren’t about strategy. They were caught in something more frustrating and harder to name. The most persistent conflicts I see between business partners as a cofounder coach might appear to be focused on operational disagreements about things like equity or product direction. But beneath these superficial topics, their emotional drivers are the same interpersonal dynamics that people bring into every close relationship. Attachment theory offers a useful frame here. Developed by psychologist John Bowlby (1969) and expanded by Mary Ainsworth (1978), the basic idea is that humans are wired for connection, and when that connection feels threatened, we respond in predictable ways. Those responses don’t pause because you’re in a business context. Cofounder relationships are attachment-based relationships. The sustained pressure of building …