PDI Design Group | 236 followers on LinkedIn. Planners, Designers, and Innovators... creating buildings and environments for a bright future. | PDI Design Group is an architecture firm based in Minneapolis, Minnesota and specializes in architecture, engineering, and design. PDI is the successor firm to the former Leonard Parker Associates (TLPA). With a portfolio of more than 50-years of architectural history, PDI continues to follow the tradition of excellence by providing modern, sustainable, and innovative designs for the 21st century.