Dennis has participated in 14 MPWs as faculty and one as a student.

He is the executive editor for environment at National Geographic Magazine and believes that environmental issues are an underlying aspect of almost every photo story.

He likes MPW because it allows photographers to find their own voice instead of simply completing assignments generated by others. While in France, he ran into three of his former MPW students. About MPW, they admitted to Dimick, "That was the worst week of my life at that time, but I had no idea how it would change my life."