A method for transmission in a mobile telecommunications system, comprising: Performing a scanning or network listening operation in a first cell to monitor transmissions of one or more neighbouring cells, and determining scrambling codes of said transmissions and determining timing offsets, with respect to the timing of said first cell, of said transmissions; and Providing (24, 26) a scrambling code and a timing offset for a scrambling code for use in transmissions within said first cell, characterised by the steps of determining, either in a pre-characterisation step or in a real-time process, cross-correlation values between said codes of neighbouring cells and scrambling codes that may be employed in said first cell, and cross-correlation values as a function of timing offset between said codes of neighbouring cells and scrambling codes that may be employed in said first cell, the function comprising, for each pair of said codes of neighbouring cells and scrambling codes, offsetting the codes by the timing offset and computing a sum of the point multiplication of the codes, and selecting, in dependence on said cross correlation values, a scrambling code and a timing offset for said first cell, which has a reduced likelihood of interference with transmissions of neighbouring cells wherein in an initial characterisation process, one or more cross-correlation matrices are derived containing information as to cross-correlation values between scrambling codes that may be employed, and cross-correlation values as a function of timing offset that may be employed, and the method comprising employing said matrices as lookup tables in said steps of providing a scrambling code and timing offset. Performing a scanning or network listening operation in a first cell to monitor transmissions of one or more neighbouring cells, and determining scrambling codes of said transmissions and determining timing offsets, with respect to the timing of said first cell, of said transmissions; and Providing (24, 26) a scrambling code and a timing offset for a scrambling code for use in transmissions within said first cell, characterised by the steps of determining, either in a pre-characterisation step or in a real-time process, cross-correlation values between said codes of neighbouring cells and scrambling codes that may be employed in said first cell, and cross-correlation values as a function of timing offset between said codes of neighbouring cells and scrambling codes that may be employed in said first cell, the function comprising, for each pair of said codes of neighbouring cells and scrambling codes, offsetting the codes by the timing offset and computing a sum of the point multiplication of the codes, and selecting, in dependence on said cross correlation values, a scrambling code and a timing offset for said first cell, which has a reduced likelihood of interference with transmissions of neighbouring cells wherein in an initial characterisation process, one or more cross-correlation matrices are derived containing information as to cross-correlation values between scrambling codes that may be employed, and cross-correlation values as a function of timing offset that may be employed, and the method comprising employing said matrices as lookup tables in said steps of providing a scrambling code and timing offset. determining, either in a pre-characterisation step or in a real-time process, cross-correlation values between said codes of neighbouring cells and scrambling codes that may be employed in said first cell, and cross-correlation values as a function of timing offset between said codes of neighbouring cells and scrambling codes that may be employed in said first cell, the function comprising, for each pair of said codes of neighbouring cells and scrambling codes, offsetting the codes by the timing offset and computing a sum of the point multiplication of the codes, and selecting, in dependence on said cross correlation values, a scrambling code and a timing offset for said first cell, which has a reduced likelihood of interference with transmissions of neighbouring cells wherein in an initial characterisation process, one or more cross-correlation matrices are derived containing information as to cross-correlation values between scrambling codes that may be employed, and cross-correlation values as a function of timing offset that may be employed, and the method comprising employing said matrices as lookup tables in said steps of providing a scrambling code and timing offset.