After his graduation in 1961, Jackson started as computer science designer and consultant for Maxwell Stamp Associates in London. Here he designed, coded and tested his first programs for IBM and Honeywell computers, working in assembler. There Jackson found his calling, as he recollected in 2000: "Although I was a careful designer — drawing meticulous flowcharts before coding — and a conscientious tester, I realised that program design was hard and the results likely to be erroneous..." Information system design was in need of a structured approach.