At the moment we don’t have this functionality. However, there are a couple of workarounds that you can use:

  1. Create a project with sub-tasks and place the link to it in the master project. For instance, let’s say you have a master project named “Create a website” and the project consists of 3 phases: design, implementation, testing. You can create 3 projects: design, implementation, testing and in the “Create a website” project just place the links to them.
    1. To get the project link, right click on the project and select “Get link to this project” – 
    2. If you double click on the item name, it will open the appropriate project – 
  2. Use tags to categorize tasks. Let’s take an example described above. We have a parent task “Create a website” and 3 sub-tasks: design, implementation and testing. For each of the subtasks I would create a tag “website” and filter the items by this tag. This way I will see all the sub-tasks related to the “Create a website” task.
    1. To create an item tag, select an item and add a tag in the Details section – 
    2. To filter items by the tag, click on Sort&Filters and select the needed tag –