At the end of John Roberts Jr.’s first full year as chief justice, his tenure is taking shape, framed by sometimes conflicting goals of collegiality, continuity and change.

He leads the nation’s highest court more openly and with a lighter touch than his predecessor, the late William Rehnquist, and has quickly endeared himself to Supreme Court staff. But his imprint on the Court as an institution has been measured in small increments so far, as the realization sets in that major change — such as increasing the size of the Court’s docket and reforming the law-clerk-pooling arrangement — may take years to accomplish.