Isothermal holding experiments between the liquidus temperatures, T-L, and the solidus temperatures, T-S, were carried out on nickel-based wrought superalloys. It was found that during solidification the elements aluminium, cobalt and tungsten tend to dissolve in the gamma matrix whereas titanium, tantalum and molybdenum tend to segregate into the liquid. Molybdenum and titanium cause the formation of brittle sigma and eta phases, respectively, after prolonged holding at elevated temperatures, in accordance with the results of New-PHACOMP (new phase computation).