Requirements Engineering (RE) is a determinant of productivity and product quality. It is inherently complex due to influences from customer environment, making the requirements engineer a central role in software development processes. There are several studies investigating attributes of great software practitioners. Knowing them is essential to help make better software engineers. However, the investigation of such attributes is still missing in RE. We believe that the current knowledge on attributes of great software practitioners might not be easily translated to the context of RE because its activities are, usually, less technical and more human-centered than other software engineering activities. This work aims to investigate which are the attributes of great requirements engineers, the relationship between them, and which strategies can be employed to obtain these attributes. We follow a mixed-method approach composed of a survey with 18 practitioners and follow up interviews with eight of them. Investigative ability to talk to stakeholders, judicious, and understand the business are the most commonly mentioned attributes amongst the set of 22 attributes identified, which were grouped into four categories. We also found 31 strategies to improve RE skills. The attributes, their categories, and relationships are organized into a conceptual framework. The relations between attributes and strategies are represented in a Sankey diagram. Software practitioners can use our findings to improve their understanding about the role and responsibilities of requirements engineers.