Purpose: The purpose of this paper is to describe the selection process and criteria that led to the implementation of the Koha 3.0 library management system (LMS) at the Complementary and Alternative Medicine Library and Information Service (CAMLIS), Royal London Homoeopathic Hospital. Design/methodology/approach: The paper is a report based on internal documentation. Findings: Koha 3.0 was selected because the GNU licence (open source) was considered more future-proof than proprietary products, and more open to customisation to meet the special needs of the library. Research limitations/implications: The library is still in the early stages of the LMS implementation. How far the Koha LMS implementation has met the library's needs will only become clear after at least one year's use. Practical implications: The conclusions drawn from this report relate to the concept of implementing an open source LMS. The author will report on the completed implementation in a year's time. Originality/value: This is amongst the first implementations of Koha in the UK. Experience and conclusions from this installation might influence decisions at other libraries.