ASM International, Chicago Regional Chapter
- Materials engineers and scientists that network to advance industry, technology and applications of metals and materials. Features a meeting calendar, member news, job postings, links, and services.
- http://www.asmchicago.org/

Institute for Objective Measurement (IOM)
- Seeks to bring understanding to psychological and educational measurement in the human sciences. Provides information on certification program, publications, workshops, and Rasch measurement.
- http://www.rasch.org/

American Statistical Association, Chicago Chapter
- Serves as a clearing house of information of interest to area statisticians. Meeting calendar, presentation slides, and contacts are featured.
- http://www.chicagoasa.org/

Chicago Chapter Society for Neuroscience
- Offers support, education and networking to neuroscience professionals. Features events calendar, announcements, and contacts.
- http://www.chicagosfn.org/

Chicago Group of the Sierra Club
- Environmental group dedicated to protecting the area's natural resources, providing information through monthly meetings, newsletters and organizing outings and volunteer opportunities.
- http://illinois.sierraclub.org/chicago

Chicago Wilderness
- Partnership of 88 public and private organizations that have joined forces to protect, restore and manage protected natural lands in the Chicago metropolitan region and the plants and animals that inhabit them.
- http://www.chiwild.org/

Friends of the Chicago River
- Group fostering the vitality of the Chicago River for the human, animal, and plant communities within its watershed.
- http://www.chicagoriver.org/