Search for new flat-spectrum radio sources

22 GHz continuum observations with the Metsahovi Radio telescope are used t o identifying new flat spectrum radio sources selected from lower frequency survey data. The sample is complete to sources with a flux higher than 0.5 Jy at 1.4 GHz, alpha greater than or equal to -0.5 between 1.4 and -4.85 G Hz, declination from 0 to +75 degrees and sources more than 20 degrees from the galactic plane. Additional strong sources from the 5 GHz, survey were observed to get the sample as complete as possible down to 1.0 Jy at 22 GHz for extrapolation of source counts to lower flux levels. The new flat spec trum sources will be added to our monitoring sample and their duty cycle wi ll be studied for the coming gamma -ray observatiories AGILE and GLAST.