This paper describes experimental work on the aerodynamic features of a chain grate stoker link mat and interprets and analyses the results of flow visualisation and associated quantitative measurements. Particular attention was paid in the experimental work to local air flow characteristics by using smoke tracer techniques on an actual link mat and pulsed wire anemometry on an enlarged scale model mat. Examples of jetting flow, recirculation, wakes and eddies of long residence time have been recorded for typical chain grate combustion air flow rates. Such information represents a significant step forward from the traditional empirical development and allows the proposal of improved, commercially applicable grate link designs for the enhancement of the role of coal in a competitive fuels market where environmental legislation is ever tightening. The results are being used in a subsequent part of a project to develop a new design of stoker mat link.