Monitoring protein abundance using Mass Spectrometry within cells is a widely used technique and commonly used. The abundance however is a static measurement with no real information about the dynamics of those proteins and so clearly missing important information. In order to get a better appreciation of the intricacies of protein homeostasis and turnover, we employed a SILAC labelling approach. Mouse tendon fibroblasts were grown in 13C lysine SILAC for 48 hours and then the incorporation of SILAC heavy label was measured. This provided a large amount of data which could be analysed to provide information about protein turnover.