How are assignments determined for 3-Star and 4-Star Generals/Admirals?

A few thoughts:
- The number of GOs in the Army to about 400 total: 10-12 four stars, 50 or so three stars, 140 or so two stars, and about 200 one stars.
- One and two stars go through a promotion board process as I understand it. Senate confirmation is required for all officer promotions but normally approved as a list, not individuals. A GO must be promoted within 5 years or must retire and must hold the rank for a year before being eligible for the next rank. Three and four stars are nominative positions which means the President nominates and the Senate must confirm individually. If the President nominates a GO for a new position but does not nominate the GO in that position for a new job then the GO is effectively retired.
- Promotion board members consist of officers 1-3 ranks higher than the personnel packets going through the boards. I am told this is similar to senior GOs. The current 2 and 3 stars are on the one star board; current 3 and 4 stars are on the two star board. Don't know if there is a 3 star board but do think the current 4 stars are the ones making the recommendation for SECDEF and POTUS.
- The short story is that the numbers are smaller for 3 and 4 stars so the process can be a bit more informal but the same basic rules apply as for lower ranks just with more formality due to greater numbers. Have great performance, show good potential to serve at the next higher level, have a good professional reputation, and be a team player.

CPT Aaron Kletzing - Something I learned from being both an Aide and an XO to an Army three-star and physically watched the process develop (as well as having family members who are General Officers and have discussed it with them).

Promotions and assignments for General Officers (GO) are, for the most part, managed by more senior GO. While the promotion board for BG/0-7 is more similar to the board process used for non-GO than for selection to MG/0-8, the GO family plays a very large part in the board results by direct input to members of the selection board. Of course, branch and other requirements dictate the number promoted by specialty, to a large degree, especially in the smaller specialties, to ensure specialty slots can be manned by the appropriate ranked person. In addition, the "social engineering" goals ( race, sex, etc.) must also be achieved.

For promotion to MG/0-8, there is a board convened but all active LTG/0-9 get a "vote" via a form sent out listing all BG being considered. Each of the LTG/0-9 gets to vote "yes" or "no" (or no vote if they do not know them). The results of that vote is provided to the selection board.

LTG/0-9 are selected by GEN/0-10.

Of course, all selections must be approved by the Senate before they are validated and the list published.

Assignments work in a similar manner, with tremendous input for GO responsible for the positions assignments are being made (i.e., CINCs, MACOMs, etc.). Key assignments (and at that level, most are) also get input from the service secretaries and defense secretary.

I don't know, but I bet their assignment managers are more responsive then mine.