Hassan serves both public and private sector clients with their defined benefit pension and retiree medical plans. His consulting expertise includes actuarial valuations for funding and accounting purposes, plan design and administration, benefit improvement analysis, annual compliance with government reporting requirement for defined benefit plans, experience studies, evaluation of the cost impact of proposed legislation, plan terminations, employee communications, computer modeling, and retiree medical valuations including costs under GASB Statement 45. In particular, he has extensive experience in creating interactive pension cost computer simulation models for the public and private sector.

Hassan's diverse group of clients have included not-for-profit organizations, manufacturing firms, publishing companies, statewide and municipal public retirement systems, and the federal government, in particular the Pension Benefit Guaranty Corporation, for whom he developed a computer model used in determining unpaid contributions and bankruptcy claims for plans in distress.