A promoter for high level and sustained expression is provided which can be used for gene expression of chosen sequences in general. In particular, a nucleic acid construct comprising a hCEF1 promoter operably linked to a sequence for expression is provided, where the hCEF1 promoter comprises: (i) a human CMV enhancer operably linked to a human EF1 a promoter (ii) a functional fragment of (i) or (ii) a functional variant of (i) or (ii).