On this trip, Hong Kong SAR is the main airline in Vancouver, so free luggage and additional baggage fees must comply with our rules. That`s because the ultimate goal is in the U.S. — and the rules for the first marketing company, Cathay Pacific, apply to the entire trip. Today there are so many different types of agreements in the aviation sector. While the exact terms vary with each partnership, I think the simplest way to summarize it is that an interline agreement is like a friendship, a codeshare agreement like an engagement, a joint venture like a marriage, and an alliance is like a big family where everyone does their own thing. Note that airlines typically form joint ventures between certain regions, which is different from a full merger. A few years ago, Delta decided to unsubscribe from an interline agreement with American because they discovered that American booked them more passengers than the other way around during irregular operations. A codeshare agreement does not allow airlines to coordinate on prices and capacity. If a codeshare agreement is like dating, then a joint venture is like getting married. A joint venture agreement is a massive company decision, which usually requires significant state authorisation. When airlines set up a joint venture, they coordinate prices and schedules and have a revenue-sharing agreement. If you`re wondering what interline agreements are, it means cathay Pacific can mark the luggage and transfer it to another airline to avoid re-checking. .