AbstractWhy was “chaff temper” used in pottery production? The possible reasoning behind the practice of intentionally adding organic matter (various plant parts and plant-containing materials) to the clay paste when making pottery is explored by studying four Early Neolithic open settlements. Located in contrasting regions, northwest and southwest Bulgaria, they have contrasting geological settings, altitude, climate, and “pottery styles.” Ceramic fragments containing vegetal remains (charred, semi-charred parts, imprints, and phytoliths) found both on the surface of the vessels and within the body clay are studied in hand specimens, thin-sections and by using scanning electron microscopy. Whether the addition of “organic temper” was an actual functional prerequisite (e.g. caused by technological limitations of the local clays, the vessels’ use, etc.), and how to interpret the variable contents and types of vegetal remains within the clay fabrics, are the main questions discussed within a broader context. The observed variability raises awareness of a series of potential biases when interpreting vegetal remains in Early Neolithic Southeast European pottery. This study not only tackles the interrelation between two major Early Neolithic cycles – ceramic technology and agriculture – but also reveals the potential to examine the synergies between specifically technological, agricultural, and environmental study aspects. It demonstrates the intrinsically intertwined crafts and husbandry activities, technological landscapes, decision-making strategies, and subsistence patterns, all within site-specific environment. It also frames a debate on such inclusions’ strictly technological significance, their role as a cultural factor embodied in social behaviour, or completely accidental presence in the clay fabrics, and a whole spectrum in between.