On the International Space Station (ISS), extravehicular activities are major events in the building and maintaining of the orbital laboratory, and are performed to install new components, re-wire systems, modules, and equipment, and to monitor, install, and retrieve scientific experiments.

Due to the complexity of building a station in space, space agencies train astronauts extensively, preparing them to encounter surprises during spacewalks, teaching them how to assemble special tools and equipment, and carefully coordinating every activity during spacewalks. From 1998 to 2005, thirty-seven Space Shuttle missions were scheduled to assemble, outfit and begin experiments and research aboard the station.

The initial spacewalk to begin the assembly of the International Space Station was held on 7 December 1998, following the launch of the first section of the station, Zarya, from Baikonur Cosmodrome, Kazakhstan, on 20 November 1998. The spacewalk attached the U.S.-built Unity node to Zarya. The longest spacewalk was performed on 11 March 2001, when STS-102 crew members Susan J. Helms and James S. Voss conducted a full spacewalk, and then returned to the airlock, but remained in their suits ready to exit the airlock again in case the robotics operations ran into problems. The total time for that spacewalk was eight hours and fifty-six minutes.

As of 2 December 2021, there have been 245 spacewalks devoted to assembly and maintenance of the International Space Station totaling 1548 hours and 26 minutes. Thirty-seven of those spacewalks were performed from a shuttle, ninety-three from the Quest Joint Airlock, thirty-two from the Pirs docking compartment, and two from the transfer compartment at the forward end of the Zvezda service module.ISS status report 12/23/08 states that sixty-six EVAs have been from Quest. However, all NASA references verify that only sixty-five EVAs have been from Quest, as of the Expedition 18 EVA on 112 March 2009.

*denotes spacewalks performed from the Pirs docking compartment in Russian Orlan suits. ^denotes spacewalks performed from the Poisk module in Russian Orlan suits. †denotes spacewalks performed from the visiting Space Shuttle's airlock. ‡denotes the one EVA and one IVA performed from the transfer compartment at the forward end of the Zvezda Service Module. All other spacewalks were performed from the Quest airlock. ISS Expedition spacewalks are separated from shuttle spacewalks by a separator.

1998–1999

# Mission Spacewalkers Start (UTC) End (UTC) Duration1.STS-88EVA 1† Jerry L. Ross James H. Newman7 December 199822:108 December 199805:317 hours, 21 minutesConnected computer and electrical cables between the Unity node, the two mating adapters attached to either end of Unity, and the Zarya Functional Cargo Block (FGB).2.STS-88EVA 2† Jerry L. Ross James H. Newman9 December 199820:3310 December 199803:357 hours, 02 minutesInstalled two box-like antennas on the outside of the Unity module that are part of the S-band early communications system.3.STS-88EVA 3† Jerry L. Ross James H. Newman12 December 199820:3313 December 199803:326 hours, 59 minutesChecked on an insulation cover on a cable connection on the lower Pressurized Mating Adapter (PMA 2) to make sure it is fully installed, attached EVA tools on the side of Unity'''s upper mating adapter (PMA 1) in preparation for future EVAs, and inspected Orbiter Space Vision System targets on Unity''.4.STS-96† Tamara E. Jernigan Daniel T. Barry30 May 199902:5630 May 199910:517 hours, 55 minutesTransferred and installed two cranes from the shuttle's payload bay to locations on the outside of the station. Installed two new portable foot restraints that will fit both American and Russian space boots, and attached three bags filled with tools and handrails that will be used during future assembly operations.

2000

# Mission Spacewalkers Start (UTC) End (UTC) Duration5.STS-101† James S. Voss Jeffrey N. Williams22 May 200001:4822 May 200008:326 hours, 44 minutesInspected and secured U.S.-built cargo crane known as the Orbital Replacement Unit Transfer Device, completed assembly of a Russian cargo crane called Strela, and replaced one of Unity's two early communication antennas.6.STS-106† Edward T. Lu Yuri Ivanovich Malenchenko11 September 200004:4711 September 200011:016 hours, 14 minutesAttached cabling that integrated the Zvezda module fully to the rest of the ISS, and constructed and attached a magnetometer that serves as a backup navigation system for the station.7.STS-92EVA 1† Leroy Chiao William S. McArthur15 October 200014:2715 October 200020:556 hours, 28 minutesConnected two sets of cables to provide power to heaters and conduits located on the Z1 truss, relocated two communication antenna assemblies, and installed a toolbox for use during future on-orbit construction.8.STS-92EVA 2† Michael E. Lopez-Alegria Peter J. K. Wisoff16 October 200014:1516 October 200021:227 hours, 07 minutesInstalled the Pressurized Mating Adapter (PMA)-3 docking port, and prepared the Z1 truss for the installation of the solar arrays.9.STS-92EVA 3† Leroy Chiao William S. McArthur17 October 200014:3017 October 200021:186 hours, 48 minutesInstalled two DC-to-DC converter units atop the station's Z1 Truss.10.STS-92EVA 4† Michael E. Lopez-Alegria Peter J. K. Wisoff18 October 200015:0018 October 200021:566 hours, 56 minutesRemoved a grapple fixture on the Z1 truss, deployed a Z1 utility tray, Manual Berthing Mechanism latches for Z1 were cycled and opened, and demonstrated the Simplified Aid For EVA Rescue (SAFER) pack's abilities.11.STS-97EVA 1† Joseph R. Tanner Carlos I. Noriega3 December 200018:354 December 200002:087 hours, 33 minutesAttached the P6 truss to the Z1 Truss, and prepared the solar arrays for deployment. Prepared the radiator for the power system deployment.12.STS-97EVA 2† Joseph R. Tanner Carlos I. Noriega5 December 200017:215 December 200023:586 hours, 37 minutesConfigured the space station to use power from the P6. Positioned the S-band antenna for use by the space station. Prepared the station for the arrival of the U. S. Laboratory, Destiny.13.STS-97EVA 3† Joseph R. Tanner Carlos I. Noriega7 December 200016:137 December 200021:235 hours, 10 minutesPositioned a floating potential probe to measure the plasma field surrounding the space station, performed repair work to increase tension in the starboard solar array blankets that did not stretch out completely during deployment, and installed a centerline camera cable outside the Unity node.

2001