Kaplan brings to Mallesons more than 40 years' experience in dispute resolution. This includes running a practice at the London Bar, working as a government lawyer in Hong Kong, practising as a Queens Counsel in Hong Kong, and working as the judge in charge of the Construction and Arbitration list of the Hong Kong High Court. For the last 14 years he has worked solely as an international arbitrator.

Kaplan was also a council member of the International Committee for Commercial Arbitration (ICCA) and the Australian Centre for International Arbitration (ACICA). He was previously president of the Chartered Institute of Arbitrators, chair of the then Hong Kong branch of the Chartered Institute of Arbitrators, and chairman of the Hong Kong International Arbitration Centre (1991-2004).