Agile focuses on delivering small increments of the project quickly. Unlike, in traditional practices, project development is initiated after gathering complete requirements. There are different techniques that are used for requirement engineering in agile. Few techniques includes, Extreme programming, Scrum and Feature-Driven Development. This research discusses the problems faced in requirement engineering in agile. Requirements variability and team size are few such problems faced in agile. A comparison of traditional and agile practices is presented in later sections through survey. The survey was filled by IT professionals in Pakistan and results were analyzed. The results indicate that requirements variability causes main problem in requirement engineering process. In addition, good customer relationships help to gather requirements effectively.  Teams working in agile are quite satisfied by the customer as compared to teams implementing traditional practices. Moreover, the ways through which efficiency can be attained in requirement engineering is presented. There are different techniques such as, use cases and prototyping that can be used for requirement engineering for efficient results.