Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Mueller Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Mueller Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Mueller Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Robert S. Mueller III, the special counsel, has marshaled prosecutors, F.B.I. agents and other lawyers to investigate Russia’s 2016 election interference and whether any Trump associates conspired. The team has secured indictments against dozens of people and three companies, one trial conviction and a handful of guilty pleas in the highest-profile political inquiry in a generation.

Each of the core prosecutors has a specialty, like political corruption, hacking or money laundering, many of which have featured in indictments. They come from familiar places: the Justice Department’s criminal division, federal prosecutors’ offices in New York and around Washington and a law firm where Mr. Mueller worked.

The makeup of the team has shifted as prosecutors and others have departed and some aspects of the investigation are wrapping up. Here is a guide to the key prosecutors and what we know so far about the cases they worked on.

The Team

Robert S. Mueller III Special counsel Mr. Mueller was appointed in the spring of 2017 to oversee the investigation into Russia’s election interference and whether any Trump associates conspired. Having served for decades in law enforcement, Mr. Mueller was previously best known for his 12 years as the director of the F.B.I., where he reshaped the bureau to fight terrorism after the Sept. 11 attacks. Zainab N. Ahmad Along with Brandon L. Van Grack, who has left Mr. Mueller’s team, Ms. Ahmad prosecuted Michael T. Flynn, the president’s first national security adviser. They helped secure a plea deal and Mr. Flynn’s cooperation. During her time as a federal prosecutor in New York, Ms. Ahmad built her reputation by successfully pursuing high-profile terrorism convictions. Greg D. Andres A prominent trial lawyer, Mr. Andres led the special counsel’s team at the trial of Mr. Manafort and helped secure Mr. Manafort’s plea deal ahead of what would have been a second trial. Mr. Andres also assisted in the guilty plea of Alex van der Zwaan, a lawyer who was charged with lying to investigators in the case. Mr. Andres made his name as a trial attorney handling complex money laundering cases. He once was targeted in an assassination plot by a mob boss who was upset Mr. Andres had subpoenaed his wife. Lawrence Atkinson Mr. Atkinson secured the plea agreement from Mr. Cohen and the grand jury indictment of 13 Russians who carried out part of Moscow’s interference effort. He also played a role in the sentencing of Richard Pinedo, a California man who unwittingly aided the interference. The son of a journalist, Mr. Atkinson is one of the youngest members of the Mueller team. He graduated from law school eight years ago and joined the Justice Department’s national security division. Michael R. Dreeben A leading expert in criminal law who has made more than 100 oral arguments before the Supreme Court, some as deputy solicitor general, Mr. Dreeben is handling pretrial litigation for the office. His aim is to defend the mandate of the special counsel’s office from legal attacks in court and to help prevent the office from losing cases on appeal. Andrew D. Goldstein Mr. Goldstein worked on Mr. Cohen’s case and handled the sentencing of George Papadopoulos, a Trump campaign aide, and some grand jury questioning of associates of Roger J. Stone Jr., a longtime informal adviser to Mr. Trump. Previously, Mr. Goldstein led the public corruption unit at the United States attorney’s office in Manhattan, where he prosecuted Sheldon Silver, the former New York Assembly speaker who was convicted in 2015 on corruption charges. Mr. Goldstein worked as a journalist before he became a lawyer, and former colleagues at Time magazine recalled how he would bring loaves of bread baked in his bread-making machine to share. Adam Jed Mr. Jed has defended the Mueller team in pretrial litigation, including arguing that certain records should be sealed from the public in order to protect the open investigation. He joined the inquiry from the appellate staff of the Justice Department’s civil division, where he was recognized in 2013 as part of a team that successfully argued in court that the act outlawing gay marriage was unconstitutional. Scott A.C. Meisler Mr. Meisler joined the special counsel team from the appellate staff of the criminal division of the Justice Department. He has been involved in pretrial litigation, including defending the use of certain pieces of evidence collected for the Manafort trial. Elizabeth B. Prelogar Ms. Prelogar, the office’s resident Russian speaker, joined the team from the solicitor general’s office and has been involved in pretrial litigation and witness interviews. Ms. Prelogar deferred her admission to Harvard Law School to pursue a Fulbright scholarship in St. Petersburg, Russia, and went on to clerk for two Supreme Court justices, Ruth Bader Ginsburg and Elena Kagan. She also once competed in the Miss America pageant as Miss Idaho. James L. Quarles III Mr. Quarles is the special counsel’s main contact with the White House, tangling with Mr. Trump’s lawyers over the questioning of the president. At 72, Mr. Quarles is one of the oldest and most senior members of the team, and he has a history in Washington: He was a Watergate prosecutor. He was also one of three lawyers Mr. Mueller brought on from WilmerHale, his former firm. Jeannie Rhee Ms. Rhee, a former assistant attorney general and another former WilmerHale colleague of Mr. Mueller’s, has had a hand in most of the special counsel’s cases: Mr. Papadopoulos’s, Mr. Cohen’s and Mr. Manafort’s plea agreements and the indictments of Russians on charges of interfering in the 2016 election. She once said that she knew she wanted to be a lawyer after a fourth-grade play in which she played an attorney who defended a piece of candy on trial for causing tooth decay. Brandon L. Van Grack Mr. Van Grack was on detail from the Justice Department’s national security division until early October and was involved in several of the most public elements of the Mueller investigation, including Mr. Flynn’s and Mr. Manafort’s plea deals, and Mr. Manafort’s convictions in his August trial. Mr. Van Grack has returned to the national security division but will still be involved in some aspects of the special counsel’s work. Andrew Weissmann One of the highest-profile prosecutors working for Mr. Mueller, Mr. Weissmann has prosecuted Mafia bosses and led the task force investigating Enron more than a decade ago. He specializes in flipping witnesses and oversaw or took part in almost every early aspect of the special counsel’s investigation, including Mr. Manafort’s prosecution and the case against Mr. van der Zwaan. Mr. Weissmann’s aggressive tactics have prompted criticism, but some defense lawyers have noted his compassionate side, and his interests outside work extend to sports — he once attended tennis camp as an adult. Aaron Zebley Considered Mr. Mueller’s closest associate, Mr. Zebley often serves as an intermediary between Mr. Mueller’s office and senior officials at the Justice Department who oversee the investigation. He was Mr. Mueller’s chief of staff at the F.B.I. and followed him to WilmerHale. Mr. Zebley was part of a team of F.B.I. agents who chased suspected members of Al Qaeda before the Sept. 11 attacks, and he is credited with getting one of the conspirators to confess in the 1998 embassy bombings in East Africa. Aaron S.J. Zelinsky Mr. Zelinsky helped secure a guilty plea from Mr. Papadopoulos and has handled grand jury questioning of associates of Mr. Stone. A federal prosecutor on loan from Maryland, he worked there for the deputy attorney general, Rod J. Rosenstein, when Mr. Rosenstein was the United States attorney for the state. Mr. Zelinsky has a bipartisan résumé: He clerked for liberal and conservative Supreme Court justices and worked at the State Department during the Obama administration.

The Investigations

Mr. Mueller has pursued a basic set of questions: How did Russia, on the orders of President Vladimir V. Putin, wage a campaign to illegally influence the 2016 presidential race? Did any Trump associates conspire with Russia’s interference? Has President Trump tried to obstruct the inquiry?

Mr. Mueller was also authorized to investigate any potential crimes he came across in conducting the investigation. He won a conviction and guilty pleas from two top Trump campaign aides, Paul Manafort and Rick Gates, for hiding their income from consulting work for a pro-Russian former leader of Ukraine and other crimes. Mr. Gates and three others also pleaded guilty to lying to investigators, and Mr. Manafort was accused of lying to prosecutors after agreeing to cooperate with the inquiry.

The special counsel’s office has also referred several high-profile cases to other federal prosecutors, including part of the inquiry into Mr. Cohen, and three cases related to foreign lobbying.

Here are some of Mr. Mueller’s cases, and which prosecutors are involved.

Michael T. Flynn Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Flynn Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Flynn Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Flynn Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Mr. Flynn, tapped as the president’s first national security adviser, asked Russia’s ambassador to the United States in late 2016 that the Kremlin hold off on escalating in response to sanctions imposed by the Obama administration over election interference.

Mr. Flynn was ousted from his job after only three weeks and admitted to lying about those conversations to F.B.I. agents during the first days of the Trump administration.

Mr. Flynn is also significant to the investigation into whether Mr. Trump obstructed justice because the F.B.I. director at the time, James B. Comey, has testified that Mr. Trump asked him to drop any investigation into Mr. Flynn.

Paul Manafort Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Manafort Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Manafort Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Manafort Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Mr. Manafort, the former Trump campaign chairman, was convicted at a financial fraud trial stemming from his earlier work as a consultant for the pro-Russian former leader of Ukraine. On the verge of a second trial, Mr. Manafort agreed to cooperate with the special counsel’s investigators and pleaded guilty to two additional conspiracy charges, but Mr. Mueller later accused him of breaching his plea deal by lying to prosecutors. Mr. Manafort’s right-hand man in Ukraine, Konstantin V. Kilimnik, a Russian Army-trained linguist accused of having ties to Russian intelligence, has also been indicted on a slew of charges, including money laundering and conspiracy against the United States.

Rick Gates Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Gates Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Gates Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Gates Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Mr. Gates was a longtime business associate of Mr. Manafort, who brought him aboard the Trump campaign. Like Mr. Manafort, he was also indicted on bank and tax fraud charges related to their work in Ukraine and ultimately pleaded guilty to two felonies and agreed to cooperate with investigators.

George Papadopoulos Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Papadopoulos Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Papadopoulos Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Papadopoulos Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

As a foreign policy adviser who lived abroad for months during the presidential race, Mr. Papadopoulos played only a bit part in the Trump campaign but a notable role in the Russia investigation. His spring 2016 meeting with an Australian diplomat in London, where he described his contact with a Russian middleman, triggered the F.B.I.’s investigation into Russian election interference. Mr. Papadopoulos was sentenced to 14 days in jail for lying to F.B.I. agents in the case.

Richard Pinedo Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Pinedo Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Pinedo Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Pinedo Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Mr. Pinedo unwittingly helped Russia wage its social media influence campaign by selling bank account information that helped the Russians and others to bypass safeguards to gain access to online financial networks. He was sentenced to six months in prison and six months of home detention.

Russian Nationals Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Russian Nationals Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Russian Nationals Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Russian Nationals Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Two groups of Russians have been indicted: a network of 13 people and three companies accused of using social media to sow discord among voters and amplify the American political divide. They also posed as political activists and stole the identities of Americans, according to court papers.

The second indictment accused 12 Russian intelligence officers in the hacking of the Democratic National Committee and Hillary Clinton’s 2016 presidential campaign.

Alex van der Zwaan Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben van der Zwaan Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben van der Zwaan Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben van der Zwaan Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Mr. van der Zwaan, formerly a lawyer for the powerful international corporate law firm Skadden, Arps, Slate, Meagher & Flom, pleaded guilty to lying to federal investigators who were interviewing him in their investigation of Mr. Gates. Mr. van der Zwaan was the first person sentenced in the investigation and served 30 days in prison.

President Trump Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben President Trump Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben President Trump Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben President Trump Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Mr. Trump’s firing of Mr. Comey on May 9, 2017, prompted the investigation into whether he was trying to obstruct the Russia inquiry. Among the episodes Mr. Mueller is examining: whether Mr. Trump’s lawyers discussed pardons with Mr. Manafort’s and Mr. Flynn’s lawyers; whether Mr. Trump tried to force former Attorney General Jeff Sessions to take back oversight of the investigation after he recused himself; and whether Mr. Trump tried to fire the special counsel himself.

Michael D. Cohen Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Cohen Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Cohen Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Cohen Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar

Mr. Cohen pleaded guilty to lying to Congress about his pursuit of the building of a Trump Tower in Moscow, a project that extended well into the 2016 presidential campaign. He also admitted that he had briefed members of the Trump family about those discussions, and that he had minimized Mr. Trump’s role in pursuing a deal. Mr. Cohen agreed to cooperate with the special counsel’s office, which could win him a lighter sentence.

Roger Stone Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Stone Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Stone Goldstein Van Grack Rhee Jed Quarles III Meisler Prelogar Ahmad Zelinsky Andres Zebley Atkinson Weissmann Dreeben Stone Van Grack Goldstein Rhee Jed Quarles III Meisler Prelogar