The success of a project can be seriously compromised if each of the key components is not planned carefully and correctly. For more and more projects nowadays, a database is one of these key components. The database, although always given attention, is often not given the thorough planning it deserves. This lack of planning at the start of a project could potentially lead to further difficulties for the development team or result in limitations in both functionality and performance once the project is completed. To help with database planning there are a number of tools and methodologies, many of which follow the plans outlined by Dr. Peter Pin-Shan Chen and use the Entity-Relationship model as a basis. Peter Pin-Shan Chen first presented the Entity-Relationship (ER) model in March 1976, in a widely read article titled “The Entity-Relationship Model – Toward a Unified View of Data.” In this article Dr. Chen proposed merging three other models, the network model, the relational model, and the entity set model into a single system that could benefit from the best of all three. (Chen, 1976) This new unified model would be composed of a number of Entities, which would be defined as a person, a place, an object, or some type of event that the database was designed to track and maintain. It is important to understand and note that entity definitions may not be well defined across the company as a department could easily define a different term depending on their point of view. For this reason it is good to ensure that these entities are well defined and that they are not used incorrectly. Entities can have a number of attributes associated with them such as additional… middle of paper… inking and the Enhanced Entity-Relationship (EER) model was created to expand the ER model. EER has added a number of useful new concepts that more accurately describe the modeled data of this new era. Many other concepts and features have been incorporated into this model, which will continue to grow and adapt as the modeled data adapts and changes. At the core, however, will remain the basic characteristics presented as the Entity-Relationship Model. Works cited Chen, P. (1976). The entity-relationship model: towards a unified view of data. ACM Transactions on Database Systems, 1(1), Retrieved from http://www.csc.lsu.edu/news/erd.pdfWitt, G. (1997, August). Is data modeling at a standstill? Database programming and design, 64 . Retrieved from http://go.galegroup.com.portal.lib.fit.edu/ps/i.do?&id=GALE|A19690038&v=2.1&u=mel b26933&it=r&p=CDB&sw=w