Software refactoring is the process of changing a software system in a manner that does not alter its external behavior and yet improving its internal structure. Model-Driven Architecture and the popularity of the UML have enabled the application of refactoring at model-level which earlier was applied to only software code. Refactoring at model level is more multifaceted and challenging than at source code level. Hence, research in this area is still considered to be in its infancy. The objective of this research was to develop a multi-view integrated approach to model-driven refactoring using UML models. The main motivation behind using multiple views for model refactoring was to utilize the inter-view relationships to bridge the gap between code and model refactoring. In this research, a single model from each UML view is composed at metamodel level to construct an integrated metamodel. Class diagram representing the structural view, sequence diagram representing the behavioral view and use case diagram representing the functional view were selected for integration. A total of eight integrated refactoring opportunities that can be used to improve the design models were proposed over the integrated metamodel along with a set of primitive refactorings that can be used to remove the proposed smells. A prototype tool called IntegraUML that performs model integration and refactoring was also developed to allow semi-automated identification and resolution of the model smells. Validation of the proposed approach was performed by comparing integrated refactoring approach with refactoring applied to models individually in terms of quality improvement through UML model metrics. A total of nine case studies were considered for empirical validation of the proposed approach. It is concluded that more opportunities can be detected using the integrated approach rather than the individual refactoring approach. Apart from this, there was a significant improvement in the design size, complexity and modularity of the individual models after the application of refactoring over the integrated model as opposed to individual refactoring. Future work to this approach can investigate on using other models in the integration, application of pattern refactoring over the integrated metamodel and empirical validation over large real-world project designs.