Estimating and bidding need to be done properly by masonry contractors if they are to succeed. Computers and related software packages greatly facilitate the completeness of the take-offs and the accuracy of the bid numbers. The user-friendly programs are relatively cheap and simple to use with minimal training. The benefits of estimating software in terms of speed and accuracy are pointed out, and the procedures used for estimating and bidding are outlined. The use of colour graphics and 3D imaging is noted. The development of particular software (Tradesmen's Masonry Software) by US mason Bill Pacetti is described. Other masonry estimating software companies in the US are listed.