In the label printing system of the present invention, a strip of adhesive-backed label stock capable of receiving a latent charge image and having a releasable backing layer is drawn continuously from a supply reel and passed successively through an electrostatic print head, a developer, a pressure fixer, and a rotary die or butt cutter for separating the printed stock into individual labels on the uncut releasable backing layer. The latent imaging of each label at the electrostatic print head is carried out at defined discrete locations on the label stock. These locations may be defined in response to a synchronization signal produced by an angular position detector cooperating with the rotary cutter. The synchronization signal is indicative of a predetermined instantaneous rotational orientation of the cutting elements on the rotary cutting member, thereby insuring that the printed label indicia are properly centered within the label edges after die or butt cutting. When die cutting is used, separate takeup reels are provided for the waste cuttings and for the finished labels on the uncut releasable backing layer.