KNiCl3 undergoes several nuclear phase transitions. The hexanonal unit cell: a x a x c changes at 287 oC into an aV3 x aV3 xc cell. Two of the three linear NiCl3 chains in the RT structure move along the c-axis reducing the K-coordination from 12 to 9. A further structural phase transition takes place between 270-260 K. The nuclear disorder (diffuse scattering) disappears at this transition. The structure orders in a super cell 5a x5a x c. magnetic order has been observed at TN = 8.7 K. This order is incommensurate. We propose to determine the incommensurate magnetic structure at T= 2K and study the magnetic critical scattering of KNiCl3 in the ordered phase as well determine the quasi 1D scattering above TN up to T= 35K.