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  在上將威廉·威斯特摩蘭(William C. Westmoreland)關於越戰的的計劃中,搜尋與殲滅行動是第二階段計劃關鍵的進攻手段。在他的三階段計劃中,首先減緩越共滲透越南的步伐;然後由守轉攻,消滅敵人;最後協助南越政府重建越南。與清掃並堅守行動一起,搜尋與殲滅行動主要計劃在1966至1967年間的第二階段計劃中實施。  具體的說,搜尋與殲滅行動一般會派遣數量為數個排、連或者規模更大的戰鬥分遣隊的美軍至村莊中的越共或越南人民軍潛伏地點。一般行動都中,都會在目標地點旁的叢林中設伏,埋伏可能包括M18A1闊刀地雷,戰術輕武器火力支援,迫擊炮支援。有時還可能有來自臨近火力支援基地Fire support base的炮火支援。  1967年2月,幾個最大的搜尋與殲滅行動在越南(西貢與13、15號公路所圍成的)鐵三角地區進行。越共軍隊的後勤基地與分部大量積聚在此地,據稱數名越共高層也居住在這裡。攻勢以1967年2月22日的章克申城行動(Operation Junction City,名稱來自堪薩斯州同名城市)展開,該行動共銷燬了數噸糧食,殲滅越共游擊隊員730名,俘虜213名。這實在是一個慘淡的數字,因為鐵三角地區的駐軍估計有10000人以上,而斬首行動也無一成功。因此從1968年開始,搜尋並殲滅與清掃並堅守行動均被順延至第三階段。搜尋與殲滅行動的數量自此上升,特別是在北越的春節攻勢後,行動的密度上升到了前所未有的高度。

  搜尋並殲滅行動有諸多缺陷。首先,"清掃(clear)"與搜尋並殲滅行動中的"殲滅(destroy)"界限模糊不清。這導致了原本進攻性較低的"清掃(clearing)"最後變成了和搜尋與殲滅行動一樣的更加暴力與野蠻的戰術。其次,其行動效率及對戰略的推進作用都受到了質疑。

  With the lack of distinction between “clearing” and search and destroy missions, pacification was not pushed. Guenter Lewey, a Professor of Political Science at the University of Massachusetts Amherst, argued that the generals and war planners severely underestimated the enemy’s abilities to match and exceed U.S. forces. Large numbers of Viet Cong troops would be killed or captured, but they were quickly replaced. Although enemy forces were initially pushed out of certain territories, as soon as the American forces left the areas, they simple returned with more reinforcements and weapons.

  The effectiveness of the mission are also doubtful. In one of the first Search and Destroy missions northwest of Dau Tieng, named Operation Attleboro, US report states that 155 U.S. soldiers were killed, while the North Vietnamese lost 1,106. In, the report also states that 282 U.S. soldiers were killed while the Viet Cong lost 1,728 guerrillas. These figures, however, should be considered in light of the methods by which they were obtained. The estimates were almost exclusively gathered by indirect means: sensor readings, sightings of secondary explosions, reports of defectors or POWs, and inference or extrapolation.
搜尋並殲滅(Search and destroy),是一種在越南戰爭中被廣泛使用的軍事戰略。簡單地說,搜尋並殲滅的流程是:利用直升機等垂直起降飛機投放地面部隊至指定地點,「搜尋」出敵軍,「殲滅」之,隨即迅速撤退至後方。這種戰術的實施很大程度上歸功於空騎突襲(air assault)戰術的成熟,這是一種基於直升機等垂直起降飛機的全新戰術。搜尋並殲滅被認為是理想的應對對叢林游擊戰的戰術。與其相對的傳統戰術是清掃並堅守(clear and hold),簡單地說,即「攻擊」並佔領敵軍所在戰略地點,(通過修築戰壕等方法)加固之,並無限期地「堅守」該地。從理論上來說,由於單純的佔領土地並不適用與越南戰爭反共產主義聯盟一方,美軍選擇了打消耗戰,通過「搜尋並殲滅」的戰術削弱越共實力。這樣一來,死亡人數的對比就成為了檢驗此戰術成果的工具。另外,搜尋並殲滅行動往往需要遵守嚴格的規定。