We describe a program for the optical identification of a representative sample of RASS sources contained in six study areas north of δ = −9 • , with |b II | > ∼ 20 • including one region near the North Galactic pole (NGP) and one near the North Ecliptic pole (NEP) and present some preliminary results. A full identification has been carried out for a count-rate and area-limited complete subsample comprising 674 sources. The ratio of "extragalactic" ( e.g. AGN, clusters of galaxies) to "stellar"

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... (e.g. coronal emitters, active binaries) counterparts was found to depend on the galactic neutral hydrogen column density, N H . In the area near the NGP (low N H ) "extragalactic" counterparts dominate, while in the area with the highest N H most X-ray sources are identified with stellar counterparts.