Abstract: For at least a decade, States, humanitarian bodies, and civil-society actors have raised concerns about how certain counterterrorism measures can prevent or impede humanitarian and medical activities in armed conflicts. In 2019, the issue drew the attention of the world’s preeminent body charged with maintaining or restoring international peace and security: the United Nations Security Council. In two resolutions — Resolution 2462 (2019) and Resolution 2482 (2019) — adopted that year, the Security Council urged States to take into account the potential effects of certain counterterrorism measures on exclusively humanitarian activities, including medical activities, that are carried out by impartial humanitarian actors in a manner consistent with international humanitarian law (IHL). By implicitly recognizing that measures adopted to achieve one policy objective (countering terrorism) can impair or prevent another policy objective (safeguarding humanitarian and medical activities), the Security Council elevated taking into account the potential effects of certain counterterrorism measures on exclusively humanitarian activities to an issue implicating international peace and security. In this legal briefing, we aim to support the development of an analytical framework through which a State may seek to devise and administer a system to take into account the potential effects of counterterrorism measures on humanitarian and medical activities. Our primary intended audience includes the people involved in creating or administering a “take into account” system and in developing relevant laws and policies. Our analysis zooms in on Resolution 2462 (2019) and Resolution 2482 (2019) and focuses on grounding the framework in respect for international law, notably the U.N. Charter and IHL. In section 1, we introduce the impetus, objectives, and structure of the briefing. In our view, a thorough legal analysis of the relevant resolutions in their wider context is a crucial element to laying the conditions conducive to the development and administration of an effective “take into account” system. Further, the stakes and timeliness of the issue, the Security Council’s implicit recognition of a potential tension between measures adopted to achieve different policy objectives, and the relatively scant salient direct practice and scholarship on elements pertinent to “take into account” systems also compelled us to engage in original legal analysis, with a focus on public international law and IHL. In section 2, as a primer for readers unfamiliar with the core issues, we briefly outline humanitarian and medical activities and counterterrorism measures. Then we highlight a range of possible effects of the latter on the former. Concerning armed conflict, humanitarian activities aim primarily to provide relief to and protection for people affected by the conflict whose needs are unmet, whereas medical activities aim primarily to provide care for wounded and sick persons, including the enemy. Meanwhile, for at least several decades, States have sought to prevent and suppress acts of terrorism and punish those who commit, attempt to commit, or otherwise support acts of terrorism. Under the rubric of countering terrorism, States have taken an increasingly broad and diverse array of actions at the global, regional, and national levels. A growing body of qualitative and quantitative evidence documents how certain measures designed and applied to counter terrorism can impede or prevent humanitarian and medical activities in armed conflicts. In a nutshell, counterterrorism measures may lead to diminished or complete lack of access by humanitarian and medical actors to the persons affected by an armed conflict that is also characterized as a counterterrorism context, or those measures may adversely affect the scope, amount, or quality of humanitarian and medical services provided to such persons. The diverse array of detrimental effects of certain counterterrorism measures on humanitarian and medical activities may be grouped into several cross-cutting categories, including operational, financial, security, legal, and reputational effects. In section 3, we explain some of the key legal aspects of humanitarian and medical activities and counterterrorism measures. States have developed IHL as the primary body of international law applicable to acts and omissions connected with an armed conflict. IHL lays down several rights and obligations relating to a broad spectrum of humanitarian and medical activities pertaining to armed conflicts. A violation of an applicable IHL provision related to humanitarian or medical activities may engage the international legal responsibility of a State or an individual. Meanwhile, at the international level, there is no single, comprehensive body of counterterrorism laws. However, States have developed a collection of treaties to pursue specific anti-terrorism objectives. Further, for its part, the Security Council has assumed an increasingly prominent role in countering terrorism, including by adopting decisions that U.N. Member States must accept and carry out under the U.N. Charter. Some counterterrorism measures are designed and applied in a manner that implicitly or expressly “carves out” particular safeguards — typically in the form of limited exceptions or exemptions — for certain humanitarian or medical activities or actors. Yet most counterterrorism measures do not include such safeguards. In section 4, which constitutes the bulk of our original legal analysis, we closely evaluate the two resolutions in which the Security Council urged States to take into account the effects of (certain) counterterrorism measures on humanitarian and medical activities. We set the stage by summarizing some aspects of the legal relations between Security Council acts and IHL provisions pertaining to humanitarian and medical activities. We then analyze the status, consequences, and content of several substantive elements of the resolutions and what they may entail for States seeking to counter terrorism and safeguard humanitarian and medical activities. Among the elements that we evaluate are: the Security Council’s new notion of a prohibited financial “benefit” for terrorists as it may relate to humanitarian and medical activities; the Council’s demand that States comply with IHL obligations while countering terrorism; and the constituent parts of the Council’s notion of a “take into account” system. In section 5, we set out some potential elements of an analytical framework through which a State may seek to develop and administer its “take into account” system in line with Resolution 2462 (2019) and Resolution 2482 (2019). In terms of its object and purpose, a “take into account” system may aim to secure respect for international law, notably the U.N. Charter and IHL pertaining to humanitarian and medical activities. In addition, the system may seek to safeguard humanitarian and medical activities in armed conflicts that also qualify as counterterrorism contexts. We also identify two sets of preconditions arguably necessary for a State to anticipate and address relevant potential effects through the development and execution of its “take into account” system. Finally, we suggest three sets of attributes that a “take into account” system may need to embody to achieve its aims: utilizing a State-wide approach, focusing on potential effects, and including default principles and rules to help guide implementation. In section 6, we briefly conclude. In our view, jointly pursuing the policy objectives of countering terrorism and safeguarding humanitarian and medical activities presents several opportunities, challenges, and complexities. International law does not necessarily provide ready-made answers to all of the difficult questions in this area. Yet devising and executing a “take into account” system provides a State significant opportunities to safeguard humanitarian and medical activities and counter terrorism while securing greater respect for international law.