The primary aim of the PhD was to identify the team technical, tactical and physical performance indicators that differentiated winners from losers during full games, halves and quarters in elite Gaelic football. A secondary aim was to examine temporal changes in performance between the first and second half of play and from the first to the fourth quarter. Video analysis was used to examine 83 technical and tactical performance indicators from 13 teams, during 16 National Football League (Division 1) and 10 All-Ireland Championship games, throughout 2014–2015. This sample included 22 games involving a reference team and their opposition. To enable benchmarking, the sample also incorporated an additional 4 games, involving teams competing in the All-Ireland Championship semi-finals and finals from 2014-2015. Player tracking technology was used to examine 11 physical performance indicators in the reference team only. Data was analysed using univariate and multivariate statistics including: principal component analysis, discriminant analysis, logistic regression and general estimating equations. Novel performance indicators were found to differentiate winners from losers in full games (defensive-counterattacking), halves (midfield-counterattacking, possession, low-press efficiency and tackle pressure) and quarters (midfield-counterattacking, possession, offensive dead ball efficiency and high-press efficiency). Temporal analysis revealed that winners were more effective at retaining possession. Conversely, losers experienced greater declines in possession characteristics and passing profiles than winners. In the reference team, temporal changes in performance were more pronounced when examined by quarter periods than by half. Physical performance levels were maintained across halves and quarters in games that were won, compared to declines in performance observed in games lost. This thesis has highlighted the team performance indicators that distinguished between winning and losing and extended knowledge of what it takes to win. Coaches and practitioners can reference the winning profiles presented, to enhance current practice and refine preparation programmes and match day strategies.