I’ve merged your post into an existing thread so that you can vote for this feature by clicking the title or scrolling to the top and clicking the purple Vote button.
Also, for my suggested workaround, see this post and the post it links to:
Thanks,
Larry
Using sections as you propose would break the board view. Kanban doesn’t work by completing sections, but by moving items from one section to another as work progresses. Doing what is proposed here would ruin it for any organization that uses kanban for production planning.
What you describe is basically just a summary task that englobes a bunch of tasks. We can already do that by adding subtasks inside a task. The problem here is that filters don’t work with subtasks so the day-to-day task management would be terrible. That solution will work best when/if Asana decides to include subtasks in filters.
A work around for now would be to turn your sections into individual projects and use portfolio view to patch everything together into one single view. Not ideal, but would probably work.
The link to the workaround is broken 
Welcome, @lch, and sorry about that! I’ve included the content directly in the post now instead of the link, so you can see it here now:
Thanks,
Larry
Not surprised, this post is 4 years old almost, and still no solution
Hard to believe that after 4 years this needed (and simple) feature has not been implemented.
Signed up for Asana Advanced. And in many ways, it is advanced. But not being able to mark sections as complete? Come on, guys… for a product that’s over 10 years old and a request that’s been around for 5 years, it’s a bit silly.
+1 +1 +1 for this feature.
Asana team - is there a reason this isn’t a possibility?
Ridiculous this hasn’t been fixed already with so many people asking for literally YEARS.