* Henderson Engineers Incorporated - A full-service mechanical and electrical engineering firm with emphasis on the success of projects and the development of long-term client relationships.
* Howard/Stein-Hudson Associates, Inc . - A traffic engineering, transportation planning, public involvement firm with offices in Boston and New York.
* Incode Pty Ltd . - Civil and structural engineers, including forensic engineering investigations into structural failure analysis.
* J M Hillman - Bridge design specialists in plate girders, historic renovations of covered bridges, prestressed superstructures and steel beam spans.
* J. P. Enterprises - Provides section bending,pipe coils,ms plate, ss plate,angle bending,channel bending services.
* Jackola Engineering and Architecture - A northwest design firm offering engineering, architecture, surveying, interior design, surveying and land use planning.
* James Davey and Associates, Inc . - Providing services in civil engineering, water resources, and surveyoring.
* Jekay International - Manufactures and exporters of railway tracks Fastenings in India including elastic fastenings, 'K' Type fastenings etc.
* Jock Valley Engineering - Provides engineering services relating to railway infrastructure including crossings, tracks, bridges, and signals.
