There are numerous benefits to developing a business entity model (also called a logical data model), early in the analysis process.  To understand these benefits, the information captured in the business entity model needs to be understood. 

To develop the business entity model, analysts document the “things” or “nouns” that the business uses or interacts with in order to accomplish their work.  Some examples of these entities might be a bond, a loan, a borrower, or a stock, a savings account, etc. 

After the entities of the business are identified, attributes which describe each entity are also identified. So a “Borrower” may have attributes like Name, SSN, Date of Birth, etc. 

Finally, the relationships between entities are identified.  A Borrower can have a Loan, so a relationship is documented between the entities Borrower and Loan on the business entity model.

One of the most impactful benefits of the business entity model is that it becomes the common language by which all project stakeholders can communicate and understand each other. As attributes and relationships are identified for each entity, everyone can quickly understand the details of the business domain regardless of the level of previous domain knowledge they may have had.

At all stages of the analysis process, this standardized language can be used to communicate more effectively.  If business process flows are being documented, the language used for each process activity can be consistent and unambiguous.  Similarly if use cases are being written, the entities identified in the business entity model can be used to ensure that concepts are communicated clearly and have only one interpretation.

Another benefit of the business entity model is how it can be used to support the design of user interfaces.  As the screen flow of a system is captured, wireframes are often developed. Wireframes are very lean representations of a screen.  They often are nothing more than a screen which has been given a name and a purpose with simple outlined borders representing areas of the screen where information will be displayed.  The type of information that will be displayed in each area can be described using the business entities from the business entity model.  This provides the business with a basic idea of the information that will appear without having to list every single field which is both time consuming and often incomplete.  Instead, if the entity Borrower is displayed in an area of the screen, the business can know that either a subset or all of the attributes of a Borrower (as defined in the Business Entity Model) will appear and be available to the user.  The exact attributes that will be needed can be determined later as the detail screen designs are developed.

The business entities are the foundation of the business language and save time and money by eliminating ambiguity which almost always arises without a documented Business Entity Model.