Nations have used economic sanctions as foreign policy tools for centuries. Policymakers have known for some time that sanctions can and usually do have multiple goals, both instrumental and symbolic. Every time policymakers in the sanctioning nation consider imposing sanctions, they should assess the nature of the target nation, what goals sanctions are most likely to achieve, how comprehensive the measures should be, and whether they should be well publicized or behind-the-scenes. Import and export sanctions usually have their maximum effect in the short term when the target nation's trading patterns are disrupted, while dissipating in the long term as new trading partners are cultivated and illegal evasion takes its toll. In contrast, the effects of financial and cultural sanctions increase over time. Market forces frequently strengthen the effects of financial sanctions. Financial sanctions can have a chilling effect on the target economy.