Cloud Computing is an ubiquitous model that enables clients to access different services in a fast and easy manner. In this context, one of the most used models is Software as a Service (SaaS), which means that software is deployed and provisioned to the customer via internet through a web browser on a pay per use mode. However, given its complexity and characteristics, such as reusability, scalability, flexibility and customization, SaaS may be defined by workflows, which consist of atomic services, or micro-services hosted geographically in different places. SaaS execution under this type of composition may lead to abnormal behavior or failures in the end user applications at runtime. This paper presents a new model of dynamic orchestration for SaaS, which aims to reduce failures or abnormal behavior of the services involved in the execution process of business application.