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The development of conservation tillage in sub-humid to semi-arid climates originated from the need to conserve soil moisture and reduce soil erosion. Descriptions of conservation tillage in the above climatic zones are generally based upon the degree of soil surface residue cover. There is a need, however, to characterize conservation tillage for humid temperature climates, especially those with a cool season, subject to excessive precipitation and high levels of crop residue. Appropriate conservation tillage practices for such regions may make judicious use of cultivation to address soil and climatic constraints, and use tillage for straw incorporation to avoid the adverse effects of excessive crop residues on the growth of the following crop. Interaction between soil type and precipitation, in humid climates, emphasizes the need to group soil or land resources according to soil tillage requirement. Major attributes of conservation tillage in humid climates would be the continuum of live soil cover especially in the non-crop period, use of mulches and residue incorporation, and speed and efficiency of crop establishment. These attributes can be achieved through minimum tillage, rotational tillage, and attention to tillage timing. Besides their ability to conserve soil, conservation tillage practices in humid regions should also address farming system sustainability in terms of energy conservation and nutrient management.