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Processing tomato yields have risen sharply in recent years due to cultivar improvement and the widespread adoption of drip irrigation. Efficient fertilization management requires balancing the increasing nutrient requirements of high-yield crops against the adverse environmental impacts of excessive fertilization. Monitoring in California tomato fields has shown that a crop uptake of approximately 2.2 kg N, 0.3 kg P and 3.1 kg K Mg-1 of fresh fruit yield was adequate to support yields in excess of 120 Mg ha(-1). Nutrient removal with harvested fruit typically represented approximately 60% (N) or 70% (P and K) of total crop uptake. High nitrogen-use efficiency is achievable, but efficient N management requires field-specific consideration of residual soil NO3-N, which, in semi-arid production areas, can be substantial. P and K fertilization requirements are best estimated by preplant soil testing. P fertilization at a rate to match expected P removal in harvested fruit should be adequate to maximize yield in fields of moderate soil P status. The likelihood of increasing fruit yield with K fertilization is high in fields with soil exchangeable K < 200 mg kg(-1), but declines with higher soil K availability. While fruit color quality may improve with K application, K fertilization for fruit quality improvement is unlikely to be cost-effective. Plant tissue analysis, while able to document current nutrient sufficiency, provides limited guidance regarding future fertilization requirements.