In the first part of the paper, microscopic plasma processes that have been discussed in the literature in relation to reconnection are reviewed. First, estimates for the thickness of the Chapman-Ferraro current layer, δ, and the diffusion coefficient, D, resulting from current-driven anomalous resistivity are derived. The basis of the estimate is a drift velocity of ions and electrons above the instability threshold and a maximum possible merging rate. The values 1.2km < δ <20 km and 0.9 · 10 12 cm 2/s < D < 1.5 · 10 13cm 2/s are found. Specific processes which may apply are ion acoustic and electron-cyclotron turbulence. Non-linear saturation levels of these processes yield D ≈ 10 12 cm 2/s, in agreement with the first estimate, and predict narrow current sheets with widths only slightly above the electron inertial length c/ ω pe . The role of MHD instabilities in this context is briefly mentioned. In the second part, evidence for eddy convection in the polar cusp region and its possible consequences for mass transport into the magnetosphere and for merging are discussed. It is suggested that reconnection is not a laminar flow process occurring mainly at the nose of the magnetosphere as in the classical picture, but that it is rather a by-product of eddy convection in the polar cusps. The eddy diffusion coefficient derived from observations is estimated to be D eddy ≈ 5 · 10 14cm 2/s. Several microscopic processes are briefly discussed that could account for ‘viscous’ dissipation of the eddies and reconnection. The latter process would have spatial scales of several 1000 km and would be highly fluctuating in time, with a typical period of a few tens of seconds.