Title: Model-Targeted Poisoning Attacks with Provable Convergence. Abstract: In a poisoning attack, an adversary with control over a small fraction of the training data attempts to select that data in a way that induces a model that misbehaves in a particular way desired by the adversary, such as misclassifying certain inputs. We propose an efficient poisoning attack that can target a desired model based on online convex optimization. Unlike previous model-targeted poisoning attacks, our attack comes with provable convergence to any achievable target classifier. The distance from the induced classifier to the target classifier is inversely proportional to the square root of the number of poisoning points. We also provide a lower bound on the minimum number of poisoning points needed to achieve a given target classifier. Our attack is the first model-targeted poisoning attack that provides provable convergence, and in our experiments it either exceeds or matches the best state-of-the-art attacks in terms of attack success rate and distance to the target model. In addition, as an online attack our attack can incrementally determine nearly optimal poisoning points. 