INTEGRAL is the first gamma-ray astronomy mission with a sufficient sensitivity and angular resolution combination appropriate to the detection and identification of considerable numbers of gamma-ray emitting sources. The large field of view enables INTEGRAL to survey the Galactic Plane on a regular (?weekly) basis as part of the core programme. The first source catalogue, based on the 1st year of core programme data (?5 Msec) has been completed and published (Bird et al. 2004). It contained 123 ?-ray sources (24 HMXB, 54 LMXB, 28 ?unknown?, plus 17 others) - sufficient numbers for a reasonable statistical analysis of their global properties. The detection of previously unknown ?-ray emitting sources generally exhibiting high intrinsic absorption, which do not have readily identifiable counterparts at other wavelengths, is intriguing. The substantial fraction of unclassified ?-ray sources suggests they must constitute a significant family of objects. In this paper we review the global characteristics of the known galactic sources as well as the unclassified objects.