Quality of life (QL) is an important outcome measure within clinical trials. This paper describes the development of a QL module for patients with liver metastases from colorectal cancer (CRC) to supplement the European Organization for Research and Treatment of Cancer (EORTC) core QL questionnaire, the EORTC QLQ-C30. Phases 1-3 of the EORTC QL Group guidelines for developing QL modules were followed. The literature search generated 71 QL issues. Semi-structured interviews with eight healthcare professionals and 47 patients from the United Kingdom, France, Germany and Austria reduced the list to 23 issues. Questionnaire items were formulated to be compatible with the EORTC QLQ-C30. The provisional module was further tested in 102 patients resulting in a 21-item module, the QLQ-LMC21 (Liver Metastases Colorectal). A combination of the core questionnaire and the QLQ-LMC21 will provide essential QL information regarding the use of treatments in both the curative and palliative settings.