The NAM began with seismic studies in the 1950s on the Dutch part of the North Sea. Interest in the area grew when the gas field in Groningen was discovered. The assumption that the southern part of the North Sea would have a similar geological structure to that in Groningen led to further studies. In 1961, the NAM made the first exploration drills off the coast of Kijkduin. This was the first sea drill in Western Europe.
The NAM is very active on the Dutch part of the Continental Plate. The company has over sixteen offshore gas production platforms. In total, there are around ninety platforms in this part of the North Sea. The NAM usually does its own work, but they also participate in exploration and production projects for other companies. More than 40% of the natural gas that the NAM produces, excluding that produced in Groningen, comes from the North Sea.