Linguistics Olympiad: Training Guide represents a unique and complex work aimed to help students and teachers alike prepare for the national and international Linguistics Olympiads. This guide identifies the most common types of problems and, for each of them, proposes a theoretical framework (basic linguistics concepts, as well as language typology data) together with a methodological approach, tailored for each type of problems, and, in the end, a selection of practice problems from past editions of national and international Linguistics Olympiads. This work is breaking new ground, being the first of its kind, featuring a large number of languages and problems, centered around the concept of problem-based learning.