A method performed in a base station of a cellular communications system to perform downlink scheduling for Multi-User Multiple Input Multiple Output, MU-MIMO, comprising: for each User Equipment, UE, of a plurality of UEs considered for MU-MIMO UE pairing, obtaining a relative beam power at the UE for each of a plurality of beams, the relative beam power at the UE for each beam being a value that represents a relative beam power of the beam at the UE relative to a beam power of a strongest of the plurality of beams at the UE; and selecting a MU-MIMO UE pairing based on the relative beam powers obtained for the plurality of UEs, the MU-MIMO UE pairing comprising a set of UEs {UE 1,...., UE N} on a respective set of beams {b 1,..., b N}, where N is an integer greater than 1, the set of UEs {UE 1,...., UE N} is a subset of the plurality of UEs considered for the MU-MIMO UE pairing, and the set of beams {b 1,..., b N} is a subset of or all of a plurality of beams available for downlink transmission at the base station; wherein selecting the MU-MIMO UE pairing comprises selecting the MU-MIMO UE pairing such that each pair of UEs, UE k and UE n, in the set of UEs {UE 1,...., UE N} satisfies: RBP k i j > Th and RBP n j i > Th where: RB P k i j = RB P k i RB P k j and RB P n j i = RB P n j RB P n i and: • RBP k ( i) is the relative beam power at the UE k for the beam, b i, selected for the UE k in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE k; • RBP k ( j) is the relative beam power at the UE k for the beam, b j, selected for the UE n in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE k; • RBP n ( j) is the relative beam power at the UE n for the beam, b j, selected for the UE n in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE n; • RBP n ( i) is the relative beam power at the UE n for the beam, b i, selected for the UE k in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE n; and • Th is a predefined threshold value. for each User Equipment, UE, of a plurality of UEs considered for MU-MIMO UE pairing, obtaining a relative beam power at the UE for each of a plurality of beams, the relative beam power at the UE for each beam being a value that represents a relative beam power of the beam at the UE relative to a beam power of a strongest of the plurality of beams at the UE; and selecting a MU-MIMO UE pairing based on the relative beam powers obtained for the plurality of UEs, the MU-MIMO UE pairing comprising a set of UEs {UE 1,...., UE N} on a respective set of beams {b 1,..., b N}, where N is an integer greater than 1, the set of UEs {UE 1,...., UE N} is a subset of the plurality of UEs considered for the MU-MIMO UE pairing, and the set of beams {b 1,..., b N} is a subset of or all of a plurality of beams available for downlink transmission at the base station; wherein selecting the MU-MIMO UE pairing comprises selecting the MU-MIMO UE pairing such that each pair of UEs, UE k and UE n, in the set of UEs {UE 1,...., UE N} satisfies: RBP k i j > Th and RBP n j i > Th where: RB P k i j = RB P k i RB P k j and RB P n j i = RB P n j RB P n i and: • RBP k ( i) is the relative beam power at the UE k for the beam, b i, selected for the UE k in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE k; • RBP k ( j) is the relative beam power at the UE k for the beam, b j, selected for the UE n in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE k; • RBP n ( j) is the relative beam power at the UE n for the beam, b j, selected for the UE n in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE n; • RBP n ( i) is the relative beam power at the UE n for the beam, b i, selected for the UE k in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE n; and • Th is a predefined threshold value. • RBP k ( i) is the relative beam power at the UE k for the beam, b i, selected for the UE k in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE k; • RBP k ( j) is the relative beam power at the UE k for the beam, b j, selected for the UE n in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE k; • RBP n ( j) is the relative beam power at the UE n for the beam, b j, selected for the UE n in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE n; • RBP n ( i) is the relative beam power at the UE n for the beam, b i, selected for the UE k in the MU-MIMO UE pairing relative to the beam power of the strongest of the plurality of beams at the UE n; and • Th is a predefined threshold value.