Commercial
Building Owners and Managers Association (BOMA) International
[ http://www.boma.org/ ]
Professional network that works with leasing, ownership and building development.
Commercial IQ
[ http://www.commercialiq.com/ ]
The largest network of commercial real estate on the internet.
Datscha
[ http://www.datscha.com/ ]
Sweden's leading provider of services for information and analysis of commercial properties.
Institute of Real Estate Management (IREM)
[ http://www.irem.org/ ]
Conducts research and provides information for those who work with income-producing properties.