**We use a combination of deskphones, PC App and Phone Apps**
Setting a rule and turning it on each time, while cumbersome, is not the end of the world. The real issue with that suggestion is that blocking calls truly blocks the call - no option to go to voice mail. Yes, it would be nice if you could set numbers 'favorites' or 'priority' and have the option of letting them thru on DND. (think Apple and their DND feature).