Eels begin their life in the Sargasso Sea and make their way to Europe, changing from glass to yellow and finally to silver eels. This amazing lifecycle is in jeopardy as the eel has seen its habitat slowly eroded by pollution and other threats over the past several decades. The EU-funded project 'Restoration of the European eel population: pilot studies for a scientific framework in support of sustainable management' (SLIME) gathered together computer modellers and eel experts to address this problem. A total of 6 different models were evaluated using real data from 10 sites spread across Europe, including eel fisheries. The models (SMEP, GEMAC, DemCam, Globang, SWAM and LVPA) used eel population dynamics to estimate stock levels within a single river catchment. The impact of fishing as well as intervention measures, such as restocking and fishery restrictions, could thus be evaluated. The models account for the various stages of the eel's lifecycle and provide complementary feedback. The experience gathered from applying the models at the 10 test sites was positive, though the SLIME participants caution that conclusions cannot be drawn for other regions. Furthermore, they stress that fine-tuning of the models with local data, where available, is absolutely imperative for accurate results. By continuing to coordinate model development and utilisation at the European rather than national or regional level, valuable insight into how to optimally restore eel stocks can be obtained.