He introduced administrative reforms only at the margins. By and large, he simply grafted the prevailing decentralized administration system, which barely worked for petty states like his native Toungoo, to the largest polity ever in the region. Indeed, it did not work for mid-size kingdoms like Ava, Hanthawaddy, Lan Na, and Siam. (Ava had always had to contend with Prome and Toungoo; Pegu with Martaban and Bassein; Chiang Mai with Chiang Saen and Nan; Ayutthaya with Phitsanulok; etc.) Now, because of the sheer size of the empire, the system was even more decentralized and stretched thinner still. At any rate, it was the only system the Toungoo kings knew, and they "had no choice but to retain it."