As a company, you want to properly manage what is available to each user. For instance: Department A may not have the same booking rights that the Department B of your company.
From the Admin Panel (gear icon) go to Job titles. Here you can adjust and filter the categories, payment methods and project per particular job title.
If you click on the eye on the right of the screen, you access the details of the job title settings. In this setting, pop-up, you can Allow and refuse the resources you previously included in the Categories, Payment methods and Projects section.
If you 'Refuse' a resource for a job title, all the users connected to this job title will not have access to this resource.
Note that if one user within this job title, can have access to this particular resource, you can enable it on his user profile.