The accelerated production campaign has become popular in recent years as a vehicle for increasing the aggregate output of a particular crop by substantially raising the per hectare yields on enough farms to make an impact on output at the national level. One could almost say that production campaigns have become a "style of development." Masagana 99 is selected as an example of a successful campaign, and those factors which appear to be necessary preconditions are available technology, a credit system, incentive prices, and political support and leadership. Activities that must be set in motion once a decision has been made to initiate a campaign include: organizing for planning, implementation, and control with a structure that goes from the local village to the highest level of government; selecting target areas and concentrating effort in them; training farmers and field technicians, and making the technicians mobile; supplying and coordinating inputs and credit; and publicity. If the preconditions are not in place, resources should be used to establish them rather than on a campaign that is likely to fail. While they require to be backed up by research and extension, accelerated production campaigns are basically promotional activities, and can be incompatible with research and extension organizations. Overshadowing all of these factors is weather, which can make or break a campaign.