1.

Match informational messages to the characteristics and situation of the target group. To influence an actor's behavior, it is important to see the decision situation from that actor's perspective. One way actors vary is in their capacities to understand information that is potentially useful to them. Individuals and groups may differ in levels of basic literacy or in quantitative and scientific sophistication, and information is most effective if it meets audiences at their own level. Audiences also differ in the kinds of information that is most useful given their particular situations—and, in some situations, the effectiveness of information depends greatly on other conditions. For example, energy conservation information has greater effect among homeowners than renters because there are more things they can do to take advantage of it, and it also accomplishes more when energy prices and other incentives give the information a greater payoff. A forecast of degree-days or precipitation for the next growing season may, in similar manner, be more useful to farmers who have a wide range of crop cultivars to choose from due to the development of sophisticated institutions of plant breeding and seed marketing; a rainfall forecast may be more useful to dryland farmers than to irrigators in the same region.

2.

In designing informational efforts, consider the entire information delivery system, not just the message and the audience. Audiences differ in the sources of information they use, consider, and trust and in their levels of concern with particular kinds of hazards and risks. Therefore, it is generally helpful to get information to audiences from sources they trust (National Research Council, 1984) and to be sure it addresses their most serious relevant concerns (National Research Council, 1996b). For example, home energy conservation programs in the 1970s and 1980s were mainly unsuccessful in attracting low-income households to participate, even if they offered strong incentives. The programs that have been most successful with these groups have disseminated information not only through mailings and the mass media but through the target populations' favored social networks, including community organizations and friendship groups (e.g., Stern et al., 1986).

Such considerations imply that any effort to inform a diverse population of recipients must consider the roles and interactions of a variety of information sources. Sometimes a division of labor is advisable among information sources, as when weather services inform local government