The present invention relates to cellular system and especially to handover between cells on different frequency carriers in an OFDM system or between cells in 2 systems adopting different radio access technologies (RAT), at least one of them being OFDM technology. A problem is the intra-cell interference impact on the quality a connected mode terminal measures in the own cell and in neighbor cells. This is a problem for cells based on OFDM technology, because intra-cell interference has no impact as compared to the inter-cell interference on the quality provided by the cell to a connected mode terminal, whereas in UTRA the intra-cell and inter-cell interference have the same impact on the quality provided. The solution to the problem is based on the insight that for cells that are located on the same site, the eNode B possess information on the power transmitted on the respective frequency carrier, and can adjust the quality as reported from the terminal on co-located OFDM cells. The adjusted quality measure enables an improved evaluation of the quality of co-located cells, for a potential handover. The invention also relates to embodiments on a 2-step handover, wherein handover to inter-frequency, or inter-RAT cell on another site is made as a handover to co-located inter-frequency/inter-RAT cell and a handover to an intra-frequency cell located at the other site.