Double taxation relief extended to agreements between specified associations; treaty benefits require tax residency certificate and prescribed documents. Section 90A permits the Central Government to adopt agreements between specified associations in India and counterparts in notified territories for granting relief from double taxation, preventing treaty shopping and avoiding non taxation, exchanging information, and tax recovery. Income that may be taxed abroad remains includible in Indian total income with relief per the adopted agreement. The Income tax Act applies if more beneficial, but the General Anti Avoidance Rule still applies. A tax residency certificate and prescribed documents are required to claim treaty benefits, with particulars set out by CBDT notification.