The Wings alliance (= brand name) doesn't exist anymore. KLM and Northwest are still linked together and have a strong/intense partnership.

KLM and Northwest have additional partners, e.g. Kenya Airways, Jet Airways are partner of KL Flying Dutchman. You can earn/redeem miles for these airlines.
Kenya Airways and Jet Airways are also partner of a KLM/Northwest-RTW. Emirates is partner of this RTW, too. It is not possible to earn miles In KL Flying Dutchman for flights on Emirates (during the RTW).

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