Later, he joined the judicial services in 1978 and worked as judge in district judiciary in different capacities till his elevation as SHC judge in 1997. In Sindh High Court he also worked in administrative capacities including Registrar.

Justice Sherwani visited Singapore subordinate court as part of a pilot project run by Asian Development Bank in ‘Access to Justice’ program. Having attended a workshop in Manila on case flow management, he successfully applied the case flow management techniques in District courts Karachi Central, East and Hyderabad which drastically reduced the back log of cases.

Justice Sherwani pioneered work in court automation and on-line court proceedings in District East and Hyderabad. It included on-line monitoring of the court work by the court administrators. The program was later adopted by Federal Ministry of E-Government, Government of Pakistan.