The 2005 joint Cryogenic Engineering Conference and International Cryogenic Materials Conference (CEC-ICMC) was held at the Keystone Resort and Conference Center in Keystone, Colorado, from August 29th to September 2nd, 2005. We celebrated the 50th anniversary for the CEC and the 30th anniversary for the ICMC. To mark these milestones, CEC-ICMC returned to Colorado, the site of the first joint meeting. Over 700 attendees from 24 countries enjoyed the technical program, industrial exhibit, and special events. There were over 450 papers presented in plenary, oral, and poster sessions. All papers were peer-reviewed. Papers in the ICMC part of the conference present the latest information on materials and their properties used in cryogenic temperatures. Topics include the physical and mechanical properties of metals and alloys at cryogenic temperatures, insulation materials used in magnets for large-scale applications, recent developments in the conventional low-temperature superconductors, YBCO coated conductors, Bi-based superconductors, and MgB2 conductors. Conductor stability and AC losses as well as superconductor applications were also covered at this conference.