OBJECTIVES: PROQOLID was developed in 2002 to provide all those involved in health care evaluation with a comprehensive and unique source of information on Patient-Reported Outcome (PRO) and Health-Related Quality of Life (HRQL) measures available through the Internet. The objective of this study is to review the evolution of content, structure, and functionalities of PROQOLID since 2002. METHODS: The archives of PROQOLID were searched to retrieve the database just before its launch and to compare its content and structure as it was in April 2012. RESULTS: The first database, then known as QOLID, was retrieved. It included 313 instruments (32 generic and 281 disease- or condition-specific). Instruments specific to oncology were the most frequent (54). The structure had three categories: contact, conditions of use, and a copy of the questionnaire. By comparison, the April 2012 database includes 714 instruments (128% increase, with 100 generic and 614 specific), with an increase of almost 40 instruments each year (up by 401 in 10½ years). Instruments specific to nervous system diseases are the most frequent (141), reflecting the evolution in the field (e.g., 76.7% of the neurological products authorized by the EMA have been approved since 2002). The information displayed for each instrument has been improved with the addition of five categories: translations available, descriptive information, content validity documentation, measurement properties, references, and websites. In January 2005 the database was renamed PROQOLID to reflect the wider use of the term PRO. In April 2012, a new Google-type search engine was added to make browsing more user friendly. Soon all users will have more information about instruments distributed by MAPI Research Trust. CONCLUSIONS: In just over 10 years, the PROQOLID database has considerably evolved in content and structure, and offers a range of information and services adapted to the evolution of the field.