This Modern-Style Architectural and Designer Firms list not ranked in any particular order but all have longstanding reputations here in Austin.

Alterstudio Architecture Matt Garcia Design Ruby Anne Designs
A Parallel Architecture McKinney your Architects  Sago International
Austin City Homes  Mell Lawrence Architects Specht Architects
Baldridge Architects Merzbau Design Collective  Stuart Sampley Architect
Bercy Chen Studio LP MF Architecture Studio Momentum 
Brian Dillard Architecture MJ Neal Architect Thomas Tornbjerg
Dick Clark + Associates Nic Deaver Architect Tim Cuppett 
DIG:A Architecture and Design North Arrow Studio unBoxed
FAB Architecture PGM Design Build Webber + Studio
Jay Corder Architecture Pollen Architecture Winn Wittman Architecture
KRDB Rick and Cindy Black Architects