Transform messy, unstructured data into meaningful, structured data using ellmer, Posit's R package for interacting with large language models (LLMs). LLMs can quickly convert thousands of texts, PDFs, and images into the data you need for your analysis. This talk demonstrates the practical benefits and addresses the common pitfalls of using LLMs through three examples: classifying images of Iris flowers and text descriptions of disease symptoms and crimes. Learn structured outputs, prompting strategies, model accuracy and confidence measurements, and validation techniques that blend generative AI with traditional ML concepts. Perfect for both AI-curious beginners and experienced data scientists.