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Field experiments were conducted for a period of four years beginning in 1987, to determine the efficiency with which a range of cultivation implements could produce a seedbed for combinable crops following mouldboard ploughing. Four sites were used, ranging from clays (Calcareous Gleysols (F.A.O., 1988. Soil map of the world. 1:5 000 000. Revised Legend. World Soil Resources Report No. 60, Rome) to a sandy clay loam (Orthic Luvisol (F.A.O., 1988)). Laboratory expriments were also conducted on samples of the field soils and both field and laboratory measures of the energy to produce a given tilth were compared. Results indicated that less aggressive implements, such as soil driven harrows or spring-tine cultivators, were often capable of producing seedbeds equal in quality to those of powered machines with similar or improved efficiency, but with more passes across the field. Impact and cutting of soil aggregates in laboratory tests suggested that significant improvements to field machines can be made.