Blocks and Building Kits

Atco Toys
Produces a large variety of building block sets and construction toys. Provides links to sales offices.
http://www.atcotoys.com/

DIDA Development
Makes educational electronic toy brick. Taiwan.
http://www.dida.ttnet.net

Han Nam Corporation
Producing plastic building block toys in Korea since 1990.
http://hannamcorp.en.ecplaza.net/

Kiblo
3D building blocks designed for infants and toddlers.
http://www.kiblo.com/

Learning Materials Workshop
Designs building toys using hardwood blocks, acrylic prisms, and flexible forms that develop children's thinking and imagination.
http://www.learningmaterialswork.com/

Lego Company
Producer of building blocks.
http://www.lego.com/

Ritvik Mega Bloks
Canadian manufacturer of construction block sets for infants and children to age 12.
http://www.megabloks.com/

ThinkWorks
Creates and sells educational block toys such as magnetic or mosaic games. USA.
http://www.thinkandthrive.com