Any practitioner trained in using cosmetic botulinum toxin type A for on‐label and off‐label indications must stay informed of the possible complications from treatments. Though prevention of complications is ideal, management of adverse events, when they occur, is integral for a positive patient outcome. Major long‐term complications from botulinum toxin treatment are rarely observed because the agent eventually metabolizes after 3–4 months. As such, minor complications are more commonly observed and may be problematic in the short‐term. These complications seen from botulinum toxin can be organized into three main categories: (1) injection‐related complications, (2) complications intrinsic to the toxin's pharmacologic properties, and (3) the practitioner's injection technique in specific anatomical locations. Common injection‐related complications, such as pain, swelling, bruising, a heavy sensation, and headache, are well‐tolerated and well‐managed, though practitioners may consider implementing certain techniques to help mitigate these complications. Complications due to pharmacologic properties of botulinum toxin allow for an interesting discussion of complex topics, such as the genesis of the Black Box Warning on distant migration, potency and efficacy with storage conditions, lethal dose, diffusion, and immunogenicity. In addition, injection techniques for specific anatomical locations as well as recommendations for avoiding and managing complications at each location are discussed in detail.