Despite such a promising start it was not easy going for NEC. The main reason for the initial lack of success was a simple lack of money. The club had no rich patrons or members to help them out through the hard times of the First World War. Indeed, they got no help from City Hall who tended to look down on the club as a non-catholic, socialist, even communist organisation. As a result the club had no 'fixed address' for years, and without their own ground they couldn't benefit from gate receipts. In the 1920's things began to get better and the club was able to buy some land on the Hazenkampseweg so that they finally had their own ground. This helped them to attract more members and their popularity grew, nonetheless it was still a frustrating time for the club. They were champions of the second division in 1928, 1929, 1931 and 1934 but in order to gain promotion they had to play qualifying matches which never went their way. It was 1936 before their luck changed and their dreamed of promotion to the first division became fact.

The club enjoyed three golden years before World War Two intervened and it is, nowadays, a matter for speculation how NEC's Roll of Honour would have looked if so many young men hadn't died just when the club had reached the top. They became East Holland Champions in 1939 and were third in the playoff between the four Dutch Regional Champions, ending up behind Ajax and DWS. The war put an end to league football but NEC picked up where they left off by becoming champions of East Holland in 1946, 1947 and 1949 - when they ended third again. In 1954 the introduction of professional football couldn't have come at a worse time for NEC - there were some internal problems, the club had just experienced a few bad years and as a result, of course, there was a shortage of cash. In fact they narrowly escaped a return to amateur status - the KNVB was trying desperately to cut down the number of professional clubs at the time (there were over 80 clubs in Holland) and the chopping and changing involved in their attempt to slim down the league partly contributed to NEC's slide down the tables. It took until the beginning of the 1960's before the club climbed back, undoubtedly helped by the fact that the city council, finally recognizing the importance of football to the community, started contributing financial support in 1963. In 1964 they were promoted to the First Division and in 1967 to the Premier League.

Thus began the club's longest period of success, 14,000 spectators at every match, rising to 18,000 in 1970/71 - glory years to look back on with pride (even though the club never "won" anything). Success was made possible by an excellent youth scheme and good scouting - players got a good training, played in the first team for a few years and then were sold for a lot of money ( Frans Thijssen and Jan Peters are well known examples). This kept the club going for a while but they were living dangerously in financial terms and squeezing through each year, surviving on the money earned by selling their best players and what they received from city hall.

This couldn't go on indefinitely and already at the beginning of the 1970's the strain was beginning to show. In 1974 they were relegated but bounced back the next season, even reaching 7th place in the Premier Division. This was, however, the beginning of a slow slide back down to the First Division, at first fighting each season against relegation but finally going down in 1983. They had enough spirit to come back in 1985, 1989 and 1994 but never had the players/money to stay at the top. Things became so bad that the club almost disappeared altogether. In 1981  Nijmegen City Council stipulated that they could only continue subsidising the club if the professional and amateur 'wings'of the club were separated. By 1987 the club was bankrupt and would have ceased to exist if it were not that 80% of the debts were erased so NEC could go on footballing. Henk van de Water, chairman at the time, started a sponsor scheme OSRN to give the club some breathing space and a chance to regroup and reorganise. Between 1994 and 1997 it was touch and go again, the side just managing to keep their place in the Premier League, but they hung in and surprised everyone by ending up 7th in 1998. The current outlook is a bright one  for NEC - they are healthier financially (gate receipts are growing as attendances rise - 10,000 per game) and have a new stadium which will be a fine venue for NEC and its fans for the foreseeable future.