Mergers and acquisitions, a major engine of reserve and asset growth in mining, have gained strategic importance over the last quarter-century as organic discovery has slowed and development timelines have lengthened. That period has witnessed transactions worth many billions of dollars and can be roughly divided into three peaks characterized by geo-economic shifts, commodity prices and the energy transition. The Northern Miner presents a timeline of the last 25 years of global M&A, the main drivers and some of the biggest deals.