- James Law Cybertecture International
- James Liang & Associates Limited
- James Richardson Corporation Pty Ltd - Brisbane
- James Richardson Corporation Pty Ltd - Melbourne
- James Richardson Corporation Pty Ltd - Sydney
- James Stockwell Architect
- James Tattersall
- James UK
- james&mau
- JAMESPLUMB
- Jamie Bush + Co
- Jamie Fobert architects
- Jamie Harris Studio LLC
- Jamison Architects
- jamjam architecture studio
- Jan De Nul (Italia) S.p.A.
- Jan Henrik Jansen arkitekter
- Jan Hercjuk
- Jan Kath Design