In order to fill a much needed requirement for more air warfare assets without resorting to the very capable but very expensive Tromp class ships with their massive Typhon LR and Broomstick sets, the Dutch navy was allowed to order four frigates equipped with Typhon MR and an simplified electronics suite. The ships that emerged would turn out to be roomy and very seaworthy, and would (with mid-life upgrades like a Goalkeeper installation) continue to serve well into the next century.
More than this though, with the program underway and proceeding smoothly, much more so than the Tromp class, it caught the eye of the Australian government. Their attempt at designing a light destroyer had resulted in serious mission creep, and the resulting design would be so expensive to build in Australia, that only two could be ordered. A modified version of the De Ruyter class though, would fit their requirements very well.
It proved entirely possible to fit the design with American electronics, a larger gun, and a double hangar while still retaining significant growth margins. Ultimately the Australian government ordered five Adelaide class destroyers.