ISO 27001 roles

Answer: Yes. You only have to take care to not define Senior Management as the responsible role in too much activities.

2 - If so, do I have to specify who is meant by Senior Management?

Answer: Yes. Instead of concepts like manager or process owner, Senior Management may mean one or more persons, like when you define the responsibility to project team. In these cases people, and auditors usually look for the one in the highest position, so you should make well clear what Senior Management means to your organization.

3 - If so, where do I have to do this? In which document?

Answer: You have many options where to define the Senior management. You can define them in job descriptions, in the organizational chart, or in the Information Security Policy.

These articles will provide you further explanation about roles and responsibilities:
- How to document roles and responsibilities according to ISO 27001 https://advisera.com/27001academy/blog/2016/06/20/how-to-document-r oles-and-responsibilities-according-to-iso-27001/
- Roles and responsibilities of top management in ISO 27001 and ISO 22301 https://advisera.com/27001academy/blog/2014/06/09/roles-and-responsibilities-of-top-management-in-iso-27001-and-iso-22301/

These materials will also help you regarding roles and responsibilities:
- Book Secure & Simple: A Small-Business Guide to Implementing ISO 27001 On Your Own https://advisera.com/books/secure-and-simple-a-small-business-guide-to-implementing-iso-27001-on-your-own/
- Free online training ISO 27001 Foundations Course https://advisera.com/training/iso-27001-foundations-course/