The sub-title is not quite accurate, since each administration transfer happens a bit differently. But not this different. At least in living memory there has not been a transfer to a candidate with so little political experience and who to boot was not his party establishment's choice. And that makes this a unique event. As background I'll summarize the standard transition procedures from the perspectives of policy and personnel, and then talk about some international relations issues.
The Normal Transition Process
Given how bureaucratic a country we are, it won't surprise you to learn that there is a law that prescribes the transition process--The Presidential Transition Act. It provides funding for the transition and establishes accounting procedures for outside funding raised by the president-elect.
Transition mechanics are pretty prosaic. The Economist magazine described them succinctly in one sentence, although it then editorialized a bit:
Usually, the transition from campaign to administration involves the candidate's policy wonks working from his speeches to produce a coherent platform. But Mr Trump had no serious policy advisers before his election, and most of his instincts about foreign policy are "unexecutable". [The Economist, 12/17-23/2016 "Pax Trumpiana: Allies and Interests." Since we choose nominees through primary elections, "policy wonks" are hard at work defining candidates' positions well before the conventions. Once the nominee is chosen, his or her positions are turned into the party platform.
For its part, the outgoing administration will have instructed its departments and agencies to prepare detailed briefing books describing the status of programs, funding and legislative issues, and other matters that will need attention as the new administration settles in. Obviously how well this works will depend on whether the transition is friendly or hostile. After the election final adjustments would be made to briefing materials. Since most polls suggested Mrs. Clinton would win, the briefing materials probably needed significant revision. Departments also set aside office space for the president-elect's transition team, where they could familiarize themselves with issues and flesh out the new administration's executive and legislative programs, and look at personnel and organizational changes they wish to make.
For example, last summer the State Department instructed embassies to submit reports on the status of our relationship with every country in the world and any issues requiring early action or decisions. They were then compiled into briefing materials. State Department briefers have to prepare the transition team for issues that don't appear on most domestic department agendas:
* Coordinating on urgent global crises, a process continuously updated between the election and inauguration.
* Managing congratulatory phone calls that begin pouring in immediately after the election. (Which should the president-elect receive, possible talking points, and staff to ensure accurate interpretation and keeping a record.)
* Deciding which foreign heads of state to invite to Washington and in what order. Generally focus is on close NATO allies, Israel, Japan, possibly China. This may sound petty, but is not, as these decisions signal priorities of the new administration.
* Perhaps planning for early foreign travel by the president if he or she is interested in doing so, as work on the logistics would have to begin immediately.
Well before the election each party begins vetting names of possible candidates for cabinet and sub-cabinet-level positions in order to be prepared to begin confirmation hearings as soon as possible after the inauguration. Given the increasingly contentious nature of those hearings and the need to ensure that candidates have no skeletons in their closets, doing this thoroughly is important. Even something that might seem trivial, such as whether housekeeping staff are legal and appropriate FICA taxes are paid on their behalf, is checked out. You may recall "nanny gate" from the Clinton days.
More significant is the financial disclosure information required by the Ethics in Government Act, about which we've heard so much in recent weeks. It requires that nominees for any office requiring Senate confirmation provide detailed financial information to include income, assets, transactions and liabilities. Several offices are charged with ensuring compliance with this requirement--the congressional ethics committees, government agency ethics offices (still under the control of the outgoing administration, of course) and, in the case of executive branch officials, the Federal Office of Government Ethics.
Whether a candidate must divest him or herself of investments is covered by a different law, that covering crimes and criminal activity (18 U.S. Code, Chapter 11). In essence it prohibits a USG employee from participating in decisions on any matter in which he or she, a family member, a partner, or business of theirs have a financial interest. As anyone who has been reading the press is aware, provision is already causing difficulties for Mr. Trump's nominees
Who are the people to whom these provisions apply and how many of them are there? Here's what the Constitution says:
Art. II, Section 2: "[The President]... shall nominate, and by and with the Advice and Consent of the Senate, shall appoint Ambassadors, other Public Ministers and Consuls, Judges of the supreme Court, and all other...