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We have surveyed two large samples of nearby low-luminosity AGN with the VLAto search for flat-spectrum radio cores, similar to Sgr A* in the GalacticCenter. Roughly one third of all galaxies are detected (roughly one half if HIItransition objects are excluded from the sample), many of which have compactradio cores. Follow-up observations with the VLBA have confirmed that thesecores are non-thermal in origin, with lower limits for the brightnesstemperatures around ~10^8 K. The brightest of these are resolved into linearstructures. The radio spectral indices of the cores are quite flat (alpha~0),with no evidence for the highly inverted radio cores predicted in the ADAFmodel. Spectrum and morphology of the compact radio emission is typical forradio jets seen also in more luminous AGN. The emission-line luminosity seemsto be correlated with the radio core flux. Together with the VLBI observationsthis suggests that optical and radio emission in at least half thelow-luminosity Seyferts and LINERs are black hole powered. We find only a weakcorrelation between bulge luminosity and radio flux and an apparently differentefficiency between elliptical and spiral galaxies for producing radio emissionat a given optical luminosity

Radio Cores in Low-Luminosity AGN: ADAFs or Jets?