This is in the US and I think the program is standard except for these weekly lectures and assignments. The first year (or two depending if you're full or part-time) is course work. Then there's a comp exam. Then we have a dissertation proposal. Then we work on the dissertation (reading, writing, testing). Then we have the dissertation defense.
I could have worked and some people do work on their dissertation while they're doing the coursework in the beginning. It took me a while to figure out my topic though.
Also, some people take courses while working on their dissertation if they want to learn more about another field related to their topic, but it's not required.
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