The IRS denied tax-exempt status to racially discriminatory private schools. It also established guidelines and procedures for determining whether a particular school is racially nondiscriminatory. Wright (Ps), parents of black children who were attending public schools in seven States in school districts undergoing desegregation, brought a nationwide class action in Federal District Court. They alleged that the IRS has not adopted sufficient standards and procedures to fulfill its obligation to deny tax-exempt status to racially discriminatory private schools, and has thereby harmed respondents directly and interfered with their children's opportunity to receive an education in desegregated public schools. Respondents also alleged that many racially segregated private schools were created or expanded in their communities at the time the public schools were undergoing desegregation. They also alleged that the private schools had received tax exemptions despite the IRS policy and guidelines; and that these unlawful tax exemptions harmed respondents in that they constituted tangible financial aid for racially segregated educational institutions and encouraged the organization and expansion of institutions that provided segregated educational opportunities for white students avoiding attendance in the public schools. There was no allegation that their children had ever applied or would ever apply for admission to any private school. They sought declaratory and injunctive relief. The District Court permitted intervention as a defendant by petitioner Allen, the head of one of the private school systems identified in the complaint. The District Court dismissed the complaint on the ground that respondents lacked standing to bring the suit. The Court of Appeals reversed. The Supreme Court granted certiorari.