In Brunei, is court permission needed for polygyny?

Yes. Under s.23 Chapter 217 (Emergency (Islamic Family Law) Order 1999), a man may not marry again anywhere except with the written permission of a Syar'ie Judge. The application is accompanied by a written declaration stating the grounds on which the marriage is just and necessary, present income, financial commitments and liabilities, the number of dependants including new ones, and whether the consent or views of the existing wife have been obtained. Unlike Malaysian state enactments, which list specific conditions in s.23(5), Brunei's s.23(3) gives the Syar'ie Judge a general discretion to approve if satisfied according to Hukum Syara'. Official statistics on Brunei polygyny applications were not found (consult the local authorities). See Brunei.