In our modern society we are dependent on efficient agricultural production of plants. To enable sustainable food production for a growing population, increased knowledge of how plants coordinate their resources is of key importance. As natural resources become scarce, understanding how plants assimilate and incorporate compounds through the roots is essential for engineering crops with increased nutrient use efficiency. Plants take up essential nutrients and block out unwanted compounds from the soil by means of transport across a barricade cell layer in the roots. Although this selective process is vital for plant growth, we are only beginning to understand how the mechanisms that allow the plant to take up specific compounds are controlled. By taking advantage of recent breakthroughs in identification of factors controlling the development of the critical barrier in roots of the model plant Arabidopsis thaliana, this project’s aim is to define the existence and biological function of specialized passage cells within this barrier that may facilitate selective uptake into roots. With the high degree of genetic knowledge available as well as methods suitable for single cell analysis, an investigation of the role of specific cells in plant roots is becoming feasible. A functional study of passage cells is likely to reveal novel mechanisms underlying how plants coordinate uptake of resources from the surrounding soil. Understanding these physiological aspects of plant development opens up possibilities for novel biotechnological solutions aimed at improving plant nutrient uptake.