THRESHOLD is a collaborative design studio dedicated to creating experientially rich landscapes.


We aim to connect people with their surrounding environment through thoughtful yet simple design gestures. Our design process carefully considers factors such as site context, history, ecology, and materiality to seamlessly blend interior and exterior spaces.


Located in Fort Lauderdale Florida, the studio is led by Michael Callahan and Christine Sawyer who guide a multi-disciplinary team with backgrounds in landscape architecture, environmental design and the fine arts. Our combined project experience includes a range of typologies, scales, and complexities. Our services focus on Landscape Architecture within residential, commercial and hospitality development throughout coastal Florida.


We offer a professional relationship that is open, personable and seeking to partner with teams creating meaningful landscapes. Through a process of collaboration and balancing client expectations, our work embraces the complexities of each site with clarity and integrity. In time, we seek to build a distinguished body of work that is enduring and ecologically sensitive.