diplomacy; foreign affairs
Refers to international relations, negotiation between nations, or the skill of handling people tactfully.
He travels all over the world for diplomatic work.
That person is good at diplomacy and quickly becomes friends with anyone.
door-to-door selling; canvassing
Used for sales activities where someone visits homes or offices to sell products or services. Often seen in compounds like 外交員 (salesperson) or 外交販売 (door-to-door sales).
He does door-to-door insurance sales.
A salesperson suddenly came to my house and tried to sell me a vacuum cleaner.
Japan has established diplomatic relations with many countries.
Every day he goes around visiting clients for sales.
The government is carrying out active diplomacy.
I'm planning to go out on sales calls in the afternoon.
外交 refers to diplomacy or foreign relations as an activity, while 外務省 is the specific government ministry that carries it out.
外交 usually refers to diplomacy between nations, whereas 渉外 is the broader term for handling external relations in corporate or institutional settings.
diplomatic history; history of foreign policy
canvasser; door-to-door salesman; sales representative