Seventeen Moments of Spring (Russian: Семнадцать мгновений весны, romanized: Semnadtsat' mgnoveniy vesny) is a 1973 Soviet twelve-part television series, directed by Tatyana Lioznova and based on the novel of the same title by Yulian Semyonov.

The series portrays the exploits of Maxim Isaev, a Soviet spy operating in Nazi Germany under the name Max Otto von Stierlitz, portrayed by Vyacheslav Tikhonov. Stierlitz is planted in 1927, well before the Nazi takeover of pre-war Germany. He then enlists in the NSDAP and rises through the ranks, becoming an important Nazi counterintelligence officer. He recruits several agents from among dissident German intellectuals and persecuted clergy. Stierlitz discovers, and later schemes to disrupt, the secret negotiations between Karl Wolff and Allen Dulles taking place in Switzerland, aimed at forging a separate peace between Germany and the western Allies. Meanwhile, the Gestapo under Heinrich Müller are on a search for the unidentified Soviet resident spy and his ring.

The series is considered the most successful Soviet spy thriller ever made and is one of the most popular television series in Soviet history. Two songs from the series, "Moments" and "The Song on the Far-away Homeland", received critical acclaim.

February 1945, Germany. Max Otto von Stierlitz, a respected SS-Standartenführer in the Ausland-SD, is in fact Soviet spy Maxim Isaev, who has infiltrated the German establishment many years ago. Though Adolf Hitler is determined to continue the Second World War, Walter Schellenberg convinces Heinrich Himmler to conduct secret negotiations with the Americans, hoping to reach a separate peace deal which would allow the Germans to concentrate all their forces on the Eastern Front. In the meantime, Ernst Kaltenbrunner becomes suspicious of Stierlitz, and orders Heinrich Müller to launch a covert investigation on him.

Stierlitz is ordered by Moscow to ascertain whether the Americans and the Germans have a backdoor channel and, if so, to foil any possible agreement. His mission is complicated when the house of his assistants, radio operators Erwin and Katherin Kinn, is bombed. Erwin is killed, and his pregnant wife is taken to a hospital, threatening to compromise Stierlitz. He recruits two new aides—Professor Pleischner, a former member of the German Resistance, and Pastor Schlag, a clergyman who disapproves of the regime. All the while, Stierlitz has to engage in a battle of wits with Müller, who seeks to expose him as an enemy agent. He must also maneuver between the opposing factions inside the Main Security Office, as different high-ranking officials vie for power.

After realizing Himmler and Schellenberg have sent Karl Wolff to negotiate with Allen Dulles in neutral Switzerland, Stierlitz—playing on the rivalries between the Nazi plenipotentiaries—succeeds in leaking the details of the negotiations, conducted under the code name Operation Crossword, both to Hitler and to Stalin. The Soviets, now possessing evidence, demand to end those contacts and President Roosevelt must oblige them. Himmler narrowly convinces Hitler it was all merely an attempt to sow distrust between the Allies. On 24 March 1945, Stierlitz, who managed to clear all suspicions against him, returns to his duties. The Red Army is steadily approaching Berlin.

In the late 1960s, after Yuri Andropov became the chairman of the Soviet Union's Committee for State Security, he launched a campaign to improve the service's image, which was primarily associated in the public's view with its role in the political repressions carried out by the government. Andropov encouraged a series of novels, songs, films and other works glorifying KGB agents, focusing on those serving abroad – mainly in the hope of attracting young and educated recruits to the organization. The television production of Seventeen Moments of Spring was part of this trend.

During 1965, author Yulian Semyonov, a Soviet writer of espionage books, composed the novel No Password Required (Russian: Пароль не нужен), in which he first introduced the character of Vsevolod Vladimirov – a young Cheka secret police agent who infiltrates Admiral Alexander Kolchak's staff under the alias Maxim Isaev. No Password Required became a success with readers. It was adapted for the screen in 1967, and the eponymous film attracted more than 20 million viewers. Semyonov published a sequel, Major "Whirlwind" (Russian: Майор Вихрь), during the same year. In 1968 he was invited to a meeting with Andropov, who told him he had read No Password Required and enjoyed it. After the interview, Semyonov began directly cooperating with the KGB and received access to its archives. The third novel featuring Isaev, Seventeen Moments of Spring, was inspired by a suggestion from the chairman himself; Semyonov wrote it down in less than two weeks. In the new book, Isaev was – for the first time – the chief protagonist, operating inside the German intelligence system in the guise of SS officer Stierlitz. It was decided to turn the novel into a television series already in 1969, before it was even published. The character of Stierlitz reflected Andropov's own concept of the ideal Soviet spy: calculated, modest, devoted to his country and above all an intellectual, accomplishing his mission by outwitting his enemies. Semyonov based Stierlitz primarily, although not exclusively and in a loose fashion, on a Gestapo officer turned Soviet agent, Willi Lehmann. The American-German negotiations foiled by Stierlitz were modeled after the real agreement reached by Allen Dulles and Karl Wolff during 1945, which brought about the surrender of the Wehrmacht in northern Italy on 2 May 1945. Within the novel Semyonov mentions the phrase "seventeen moments of spring" in reference to the lyrics of a song sung by Marika Rökk, a popular star in Nazi Germany.