The purpose of this research was to study how teachers do differentiated teaching in practice. The main research question was: How do Finnish teachers do differentiated teaching? It was specified with sub-questions: (1) How are the various elements of the model of differentiated teaching emphasized by teachers?; (2) Which methods do teachers use in differentiated teaching?; and (3) On what basis do teachers make decisions of differentiated teaching? The data were collected from teachers (N = 40) working in municipalities across Finland with a survey that was based on a model of differentiated teaching (a so-called five-O model by Roiha and Polso). All dimensions of differentiated teaching were highlighted by teachers. Teachers implemented differentiated teaching mainly based on students' needs. It was worrying that lack of resources appeared in teachers' answers consistently within the elements of differentiated teaching. The findings are usable in the international discussion about differentiated teaching and its implementation.