Wannen and Company was formed in November 1978 by John Wannen after serving ten years with Ernst & Young. The firm was based on many of the E&Y clients whom John served as client executive and who are still with the firm today. Wannen and Company provides tax planning, compliance, business and personal advice in a select practice which includes about 250 individual or family clients and about 100 estates, trusts, professional firms and other closely held businesses.

Professional firms (lawyers, architects, physicians and consultants) are the focus among business clients. The firm also provides financial statement reporting services, capital budgeting and various controllership support for small business.

Families with complex domestic and international tax situations are the core of the individual practice which includes a wide range of services based on client needs, including estate and trust accounting and serving as professional executors and trustees.