Objectives Guidelines produced for management of Bipolar Disorder illustrate change in evidence-base for treatment of acute and maintenance phases of illness. Our Pan-European Research Group assessed clinical practice and desired treatments amongst amongst Psychiatry trainees. Methods A semi-structured survey was piloted, and homogenous sample size (at least 50) agreed upon from each country, with 50% minimum response rate. It was distributed via web-link, questioning preference of mood stabiliser for patients, trainees themselves and factors influencing choice. Results Tables 1 summarise choices. Number (n) Percentage Drug(s) 263/224 40.8/34.8 Lithium 121/101 18.8/15.7 Semisodium Valproate 133/85 20.7/13.2 Sodium Valproate 21/50 3.3/7.8 Lamotrigine 27/18 4.2/2.8 Lithium and Sodium Valproate 10/15 1.6/2.3 Carbamezapine 24/12 3.7/1.9 2nd Generation Atypical antipsychotics 8/4 1.2/0.7 Various combinations 34/134 5.3/21 Left blank Choice of mood stabiliser for patient/themselves Factors influencing decision-making mapped onto cost, efficacy and side-effect profile (less than 4% other reasons). 66% (n=538) of respondents felt efficacy most important, 25% (n=202) felt side-effect profile most important and 3% (n=24) considered cost of most importance. Conclusions No clear difference exists in choice of mood stabiliser for European trainees and their patients, and decisions based on perceived efficacy are generally in keeping with established guidelines.