2014 – present:  AgroBioAfrica: Voluntary executing studies & missions, giving advices & lectures.

2011 – 2014 AgroBioAfrica: Freelance consultant

2006-2011 Chief of Party IFDC-CATALIST & -SEW projects (Agricultural intensification and Sustainable energy through wood in Burundi, DRC & Rwanda); Resident Representative, IFDC-Rwanda (IFDC: An International Center for Soil Fertility and Agricultural Development)

2004- 2006 Resident Representative & Principal Scientist,
IFDC-Belgium & EU

1996-2004 Director IFDC-Africa & Resident Representative, IFDC- Togo

1991-1996 Project Leader “Production Soudano-Sahélienne“, a joint research project of IER (Bamako, Mali), AB-DLO and Agricultural University (Wageningen, the Netherlands)

1987-1991 Head Department of Agro-systems Research, Agro-Biology-DLO (Wageningen, the Netherlands). During this period part-time seconded to DGIS (Directorate General for International Cooperation, Dutch Ministry of Foreign Affairs) as advisor on issues of development and environment in the Sahelian region.

1986-1987 Head Department of Vegetation Science, Centre for Agro-biological Research. (Wageningen, the Netherlands). During this period part-time seconded to the Royal Tropical Institute (KIT), Amsterdam, as advisor for the Dutch-Malian Farming Systems project in South Mali (integration of animal husbandry in crop research).

1976-1986 Senior Research Scientist & Deputy Head Department of Vegetation Science, Centre for Agro-biological Research. (Wageningen, the Netherlands). Research on rangeland and pasture development in semiarid regions and the Netherlands.

1972-1976 Associated Expert UNESCO Centre Pédagogique Supérieure (Bamako, Mali). Education and research on animal physiology and ecology.

1968-1972 Assistant Professor Department of Physics, Free University (Amsterdam, the Netherlands). Education and research on biophysics