The Twelfth International Conference on Data Integration in the Life Sciences 2017 (DILS2017) was held at Luxembourg on November 14th and 15th, 2017. The conference aim was to foster discussion, exchange, and innovation in research and development in the areas of data integration, data analytics and knowledge management for the life sciences. Researchers and professionals from biology, environment, medicine, computer science and engineering were invited to share their knowledge and experience. The conference has attracted 11 research papers, all published in a Springer book (https://link.springer.com/book/10.1007%2F978-3-319-69751-2) and were presented and discussed at the conference. Two keynotes were foreseen but had to be cancelled due to personal issues of the speakers.