A computer-implemented method for designing a first radio access network, RAN, that is to operate according to a first radio access technology, RAT, in a first frequency range, the method comprising: (i) obtaining second RAN radio signal measurements of a second RAN, wherein the second RAN operates according to a second RAT that is different to the first RAT, and/or with a second frequency range that is different to the first frequency range; wherein the second RAN comprises a plurality of second RAN base stations that operate a plurality of second RAN cells, and wherein the second RAN radio signal measurements comprise measurements by a plurality of wireless devices of radio signals on one or more frequencies from one or more of the plurality of second RAN base stations; (ii) processing the second RAN radio signal measurements to estimate corresponding first RAN radio signal measurements that could be measured by said wireless devices if each of said second RAN cells were respective first RAN cells operating according to the first RAT and in the first frequency range; (iii) forming an initial cell deployment for the first RAN based on an estimate of which wireless devices each first RAN cell provides coverage for according to said first RAN radio signal measurements, wherein the initial cell deployment comprises a subset of the first RAN cells; (iv) determining a best serving first RAN cell in the initial cell deployment for each of the wireless devices based on the first RAN radio signal measurements; (v) for each first RAN cell in the initial cell deployment, estimating the first RAN cell resource utilisation based on the wireless devices for which said first RAN cell is determined to be the best serving first RAN cell; and (vi) determining an updated cell deployment based on the initial cell deployment and the estimated first RAN cell resource utilisation for each first RAN cell in the initial cell deployment. (i) obtaining second RAN radio signal measurements of a second RAN, wherein the second RAN operates according to a second RAT that is different to the first RAT, and/or with a second frequency range that is different to the first frequency range; wherein the second RAN comprises a plurality of second RAN base stations that operate a plurality of second RAN cells, and wherein the second RAN radio signal measurements comprise measurements by a plurality of wireless devices of radio signals on one or more frequencies from one or more of the plurality of second RAN base stations; (ii) processing the second RAN radio signal measurements to estimate corresponding first RAN radio signal measurements that could be measured by said wireless devices if each of said second RAN cells were respective first RAN cells operating according to the first RAT and in the first frequency range; (iii) forming an initial cell deployment for the first RAN based on an estimate of which wireless devices each first RAN cell provides coverage for according to said first RAN radio signal measurements, wherein the initial cell deployment comprises a subset of the first RAN cells; (iv) determining a best serving first RAN cell in the initial cell deployment for each of the wireless devices based on the first RAN radio signal measurements; (v) for each first RAN cell in the initial cell deployment, estimating the first RAN cell resource utilisation based on the wireless devices for which said first RAN cell is determined to be the best serving first RAN cell; and (vi) determining an updated cell deployment based on the initial cell deployment and the estimated first RAN cell resource utilisation for each first RAN cell in the initial cell deployment.