A business analyst (BA) is a person who processes, interprets and documents business processes, products, services and software through analysis of data. The role of a business analyst is to ensure business efficiency increases through their knowledge of both IT and business function.

Some tasks of a business analyst include creating detailed business analysis, budgeting and forecasting, business strategising, planning and monitoring, variance analysis, pricing, reporting and defining business requirements for stakeholders. The business analyst role is applicable to four key areas/levels of business functions – operational, project, enterprise and competitive focuses. Each of these areas of business analysis have a significant impact on business performance, and assist in enhancing profitability and efficiency in all stages of the business process, and across all business functions.

Business analysis has been defined as "a disciplined approach for introducing change to organization" through management, processing, and interpretation of data in order to "identify and define the solution that will maximize the value delivered by an organization to its stakeholders".

A business analyst's job description tends to include "creating detailed business analysis, outlining problems, opportunities and solutions for a business, budgeting and forecasting, planning and monitoring, variance and analysis, pricing, reporting, and defining business requirements and reporting back to stakeholders".

Business analysts are involved in various business activities.. Some areas in which business analysts can have an important role are in financial analysis, quality assurance, training, business policy and procedures, market analysis, organizational development and solution testing. More specifically, business analysts analyze collected data to derive meaningful insights for the business.. This can then be used to improve business performance through identifying areas for potential growth, cost reduction, understanding customer behavior, and observing economic trends and forecasts, and then reacting appropriately.

Successful business analysts should influence the business environment by providing reliable guidance in decision making for the future through observing data which reflects the behaviour of the business in the past. Business analysts are essential at all levels of a business, as both tactical and strategic planning require analysts who help with "incremental improvements to products, business processes, and application".

Business analysts have an increasing need to provide a business with sustainable solutions. The Business Analyst "plays a key role in making sustainable choices, providing direction to business and influencing demand for specific technologies". Business analysis practices have the opportunity to use business data in a positive way, which can lead to the transition of a sustainable world.

Due to the range of applications a business analyst can have, there are specific areas in which they can function. Kathleen B. Haas describes the requirement of business analysts in four areas of business – operations focus, project focus, enterprise focus, and competitive focus.