If you have been conducting quality control checks throughout the data creation process, then this step should reveal few surprises. However, if absolute fidelity to the original source is of fundamental importance to your work, it may be worthwhile investing in a separate programme of proof-reading. Simple checks to ensure that you have captured all your original sources, and that your data have been prepared and organised as you intended, can identify potentially costly mistakes which are easy to overlook. For example, if you are creating a series of digital images to create a facsimile edition of a printed work, ensure that any sequencing of the images matches the pagination of the original analogue source. Similarly, if you are conducting a computer-assisted analysis of a transcribed text, the omission of a small but vital section could affect the validity of any results.