Abstract. – Among the Lahu people of the Yunnan-Northern Southeast Asia borderlands, the conjunction of material form and spiritual essence signifies normality, fine condition, safety and, in sentient beings, good health. The disconjunction of matter and essence betokens abnormality, poor or broken condition, danger and, in sentient beings, sickness, possibly leading to death. Consequently, Lahu peoples traditionally have interpreted physical and mental sickness in human kind as the consequence of “spirit/ soul” disturbance. Consequent upon self- or specialist interpretations of omens and/or dreams, particular instances of ill-health and, sometimes, death are attributed to the escape of spirit essence (awˬ ha) from the physical body (awˬ to), or else to an attack upon the awˬ ha by one of a legion of spirit entities that Lahu term, generically, as neˇ (cognate with the Burmese word nat). This article explores some of the explanations Lahu people offer for human sickness, the precautions they undertake to protect themselves from it and, in the event that it strikes, those they take to counteract it. These involve, principally, spirit/soul strengthening, spirit/soul recall, and the propitiation or exorcism of angered, or else inherently malevolent spirit entities. [Southeast Asia, Lahu, conception of human beings, sickness, healing]