construction Sec. 2301. Authorized Air Force construction and land acquisition projects. Sec. 2302. Family housing. Sec. 2303. Improvements to military family housing units. Sec. 2304. Authorization of appropriations, Air Force. Sec. 2305. Modification of authority to carry out certain fiscal year 2017 projects. Sec. 2306. Extension of authorizations of certain fiscal year 2015 projects. TITLE XXIV—Defense agencies military construction Sec. 2401. Authorized Defense Agencies construction and land acquisition projects. Sec. 2402. Authorized energy conservation projects. Sec. 2403. Authorization of appropriations, Defense Agencies. Sec. 2404. Modification of authority to carry out certain fiscal year 2017 project. Sec. 2405. Extension of authorizations of certain fiscal year 2014 projects. Sec. 2406. Extension of authorizations of certain fiscal year 2015 projects. TITLE XXV—International programs Subtitle A—North Atlantic Treaty Organization Security Investment Program Sec. 2501. Authorized NATO construction and land acquisition projects. Sec. 2502. Authorization of appropriations, NATO. Subtitle B—Host country in-kind contributions Sec. 2511. Republic of Korea funded construction projects. Sec. 2512. Modification of authority to carry out certain fiscal year 2017 projects. TITLE XXVI—Guard and Reserve Forces facilities Subtitle A—Project authorizations and authorization of appropriations Sec. 2601. Authorized Army National Guard construction and land acquisition projects. Sec. 2602. Authorized Army Reserve construction and land acquisition projects. Sec. 2603. Authorized Navy Reserve and Marine Corps Reserve construction and land acquisition projects. Sec. 2604. Authorized Air National Guard construction and land acquisition projects. Sec. 2605. Authorized Air Force Reserve construction and land acquisition projects. Sec. 2606. Authorization of appropriations, National Guard and Reserve. Subtitle B—Other Matters Sec. 2611. Modification of authority to carry out certain fiscal year 2015 project. Sec. 2612.