A doctoral program in business is an advanced research degree usually requiring three to five years of study beyond receiving a Bachelor's degree. The goal of the doctoral program in business or management is to provide experienced management professionals with advanced knowledge and skills so that they may embark academic careers; others join research organisations; some join consulting firms.
PhD work in business is quite challenging and in most cases those achieving a PhD in business-related fields will spend anywhere from one to three years studying advanced coursework in their chosen subject field, prior to commencing their doctoral thesis. Generally, time spent on coursework tends to be less if one has earned a relevant Master's degree first. These advanced studies may eliminate the need to take certain courses. However, some doctoral programs tend not to accept students who have not already completed a Master's degree. Others are more likely to accept students with a Bachelor's degree. The decision on who to accept into a PhD program is highly variable.
Selected majors/areas of research for a PhD in Business include

Accounting and Information Systems

Business and Public Policy

Economics

Decision Sciences

Entrepreneurship

Finance, Investment and Banking

Global Management

Management and Organizations

Marketing

Operations Management

Real Estate and Urban land Economics

Science Technology and Management

Strategic Management
Students in business doctoral program must pass a written and oral qualifying exam and then complete and formally defend a doctoral dissertation based on original research. In general, all PhD programs require that successful candidates for the degree demonstrate:

The ability to conduct independent research at a high level, leading to completion of a dissertation which is defended before a committee of scholars. Because examinations given as part of a PhD curriculum assess expert knowledge, they are created and evaluated by a committee of experts, each of whom holds a PhD degree

Proficiency in the tools necessary to carry out this research, including but not limited to computer skills and bibliographic competence

Mastery of general and specific subject matter in the field of study before a committee of scholars
Part- and full-time study options, along with various delivery modes - residential programs, distance education programs and online programs - are also available. North American PhD programs in business welcome foreign students. However, fluency in spoken and written English is critically important.