Technical efficiency has long been analysed as a measure of farm performance, however most studies are restricted to a single country case. This paper presents a comparative analysis of field crop and dairy farm performance across eight EU countries, including two New Member States (NMS), focusing on long run stability and mobility patterns. The main research question is how relative performance of farms fluctuates over time, i.e. whether poorly performing farms remain always inefficient whilst some farms are always very efficient. Results show that on average 60% of farms maintain their efficiency ranking in two consecutive years, whilst 20% improve and 20% worsen their positions, for all countries. Due to the unstable economic conditions, farms in NMS are more mobile than those in EU15.