In this techno-challenge era, integrating a project with different information technology resources (tasks, data, and people) is a critical process to deliver the project completely and professionally. The integration process and decisions affect essential project properties such as reliability, maintainability, completeness and efficiency. It touches directly the cost of the project, schedule, quality and the stakeholders. The complex nature of this process leads to apply an integration model as a guideline to deliver the project successfully. These models reflect the process of integration, data sources communication, responsibilities and documents. This survey describes these models to capture the differences and similarities between IT project integration models. The focus of attention in the comparison will be on orientation, hierarchy (structure), process, and deliverables.