delongetermijnimpact

Delongetermijnimpact is a term used in Dutch-language policy analysis to refer to the effects of policies, programs, or events whose outcomes unfold over extended periods beyond the immediate planning horizon. It encompasses environmental, economic, social, health, and technological consequences that manifest years or decades after implementation.

The term is a compact form of "de lange termijn impact" commonly encountered in discussions of evaluation, impact assessment, and future planning. It highlights the importance of considering distant outcomes when deciding on current actions.

Measuring long-term impact requires forward-looking methods such as scenario analysis, modeling, regression with long-run data, ex-ante impact assessments, and horizon scanning. Analysts use indicators across time horizons and may apply discounting to compare present costs with future benefits, though discounting is controversial.

Applications include climate policy, infrastructure investments, public health interventions, education reforms, and technological adoption. For example, a renewable energy policy may reduce emissions in 2040 and 2050 beyond near-term budgets, while also affecting employment and innovation.

Challenges include attribution over long timelines, uncertainty, data availability, changing external conditions, and normative choices about appropriate discount rates and goalposts. Caution is needed to avoid overconfidence in forecasts.

See also lange termijn impact, long-term effects, impact assessment, policy evaluation.