This document provides details on an event study examining the impact of mergers and acquisitions on stock returns. It includes a literature review on motives for acquisitions and prior empirical evidence. The study analyzes acquisitions by UK firms of domestic UK targets and cross-border EU targets from 2006-2010. The methodology section outlines using an event study approach with a 3-day event window around acquisition announcements and 200-day estimation period to calculate abnormal returns. Hypotheses test for no abnormal returns for acquirers and differences between domestic and cross-border deals.