I will talk about the possibilities of probing the electroweak scale
seesaw scenarios through low and high energy processes. My main focus will be for the seesaw scale in the range M_N ~ few GeV and M_N ~ 100 GeV - 1 TeV. In the former case various Lepton number violating~(LNV) meson decays at ongoing beam dump experiments and in the later case a variety of final states including single and multi leptonic modes in association with jets at pp, e+e-, e\gamma, \gamma\gamma colliders are useful to probe the seesaw scale. I will also talk about how a linear seesaw model which is based on two higgs doublet models can provide distinctive production mechanisms for seesaw mediators and give striking LNV signatures.