Title II of the Social Security Act (Act) provides for the payment of disability insurance benefits to those whose disability prevents them from pursuing gainful employment. The disability programs administered under Titles II and XVI 'are of a size and extent difficult to comprehend.' Approximately two million disability claims were filed under these two Titles in the fiscal year 1983. Over 320,000 of these claims must be heard by some 800 administrative law judges each year. D and Congress have established an unusually protective four-step process for the review and adjudication of disputed claims. First, a state agency determines whether the claimant has a disability and the date the disability began or ceased. Second, if the claimant is dissatisfied with that determination, he may request reconsideration of the determination. This involves a de novo reconsideration of the disability claim by the state agency, and in some cases a full evidentiary hearing. Additional evidence may be submitted at this stage, either on the request of the claimant or by order of the agency. Third, if the claimant receives an adverse reconsideration determination, he is entitled by statute to an evidentiary hearing and a de novo review by an Administrative Law Judge (ALJ). If the claimant is dissatisfied with the decision of the ALJ, he may take an appeal to the Appeals Council of the Department of Health and Human Services (HHS). Thereafter, he may seek judicial review in federal district court. Ps took a class action and sought declaratory and injunctive relief from delays encountered in steps two and three above. P was forced to wait 167 days for a reconsideration determination. He received a hearing before the ALJ 173 days after his hearing request. Another claimant waited 215 days for a reconsideration determination after his disability benefits were terminated. He was given a hearing before an ALJ 65 days after his hearing request. P argued before that the delays they had experienced violated their statutory right under 42 U. S. C. § 405(b) (1976 ed., Supp. V) to a hearing within a reasonable time. The District Court held that, as to all claimants for Title II disability benefits in Vermont, delays of more than 90 days from a request for hearing before an ALJ to the hearing itself were unreasonable. It granted partial summary judgment to P on that issue in December 1979. After the submission of additional evidence, the court considered motions for summary judgment concerning the reasonableness of delays in the reconsideration process. The evidence was factual summaries of 77 randomly selected disability cases submitted by D. The court held that the process is replete with unexplained delay. In 27 of the 77 cases, reconsideration determinations took longer than 90 days. In each of these 27, the District Court concluded that the delays were caused by agency inefficiencies and were not justified by the 'necessary steps in the reconsideration process.' It held that delays of more than 90 days in making reconsideration determinations were unreasonable and violated the claimant's statutory rights. The Court granted summary judgment for Ps on the reconsideration aspect of the case. Ps got their injunction and D appealed. The court of appeals affirmed. The Supreme Court granted certiorari.