Cancer Immunotherapy 2005 was the third international meeting organized by the Association for Immunotherapy of Cancer (AIC). About 200 participants were attracted by the excellent scientific program that consisted of overview lectures from 25 international speakers in the plenary auditorium and four guided poster sessions during both days of the meeting. The first day of the symposium mainly focused on experience with, and new perspectives in, antibody therapy. On the second day of the meeting, organized as a joint conference together with the Combined Research Grant "Mechanisms of Tumor Defense and Therapeutic Intervention" funded by the German Research Council, the participants had the chance to gain deeper insights into the principles of antigen processing and the regulation of immune responses. Further topics that were discussed mainly in the poster sessions and in the special lecture given by M. Nishimura (Chicago, USA), were "cellular therapies" and "vaccination against cancer". The lectures selected for this report aim to provide an overview of the complete scientific program and give an impression of the lively atmosphere that could be felt from the first until the last session of CIMT 2005.