A series of inoculation experiments was conducted in glasshouses in Senegal and Kenya to evaluate inoculation procedures designed to optimise nodulation and N, fixation of Calliandra calothyrsus Meisn. seedlings. Nodulation and plant growth were used as indices of inoculation success. In an experiment carried out in sterile peat/vermiculite mixture, it was established that inoculation of C. calothvrsus with an effective rhizobial strain at the low rate of 1x102 rhizobia per seedling was satisfactory for nodulation and growth, but further response occurred at rates of up to 1x109. A second experiment in (unsterilised) Sangalkam soil (Senegal) containing indigenous rhizobia demonstrated that the most successful form of inoculation was liquid inoculant applied around the root collar immediately after transplanting. This method was more successful than seed inoculation or application of alginate head inoculant. A third experiment was conducted using filtermud inoculant in Leonard jars and unsterilised Muguga nursery soil from Kenya, containing a large population of indigenous rhizobia. Application of liquid inoculant to seedlings was better than seed inoculation. On the basis of our study, we recommend that C. calothyrsus seedlings raised in the nursery should be inoculated with a liquid inoculant immediately or soon after germination.