Market clearing models based on Linear Programming are being adopted in a number of electricity markets in different countries, with New Zealand and Australia being among the pioneers in this respect. This represents an exciting development for OR, worldwide, not only because these models are controlling a sector of vital national importance, but because large sums of money are being traded, virtually in real time, on the basis of model results. Here we reflect on experience with these models, draw out some lessons, and discuss the implications of these developments for OR practice in the sector, and elsewhere.