Policymaking is a competitive process in which multiple actors try to shape what government does. Their influence depends on timing, resources, public support, and where decisions are made across the policy process.

This diagram illustrates an “iron triangle,” a common model of policy influence linking congressional committees, organized interests, and executive agencies. The two-way arrows emphasize reciprocal benefits—information, support, and policy favors—that can shape decisions across multiple stages of policymaking. Source

Key idea: competition across stages of policymaking

Policy outcomes rarely reflect one actor’s preferences. Instead, competing actors apply pressure at different points, where the “rules of the game” and decision-makers change.

Common stages where influence is exercised

• Agenda setting: defining which problems deserve government attention

• Policy formulation: developing proposals, technical details, and feasible options

• Policy adoption: passing legislation, issuing orders, or approving budgets

• Implementation: executing policy through rules, guidance, and enforcement

• Evaluation and feedback: assessing results and deciding whether to expand, revise, or end a policy

How each actor type typically influences policy

Interest groups

Interest groups seek to influence public policy to benefit members or a cause. They often target specific decision points where small changes have large effects (e.g., regulatory language or budget line-items).

• Agenda setting: elevate issues using research, advertising, and media outreach

• Formulation: provide policy expertise, draft language, and data to officials

• Adoption: target key legislators/committees and mobilise members in pivotal districts

• Implementation: monitor agencies, submit comments, and push for favourable rules

• Evaluation: highlight successes or failures to defend or attack existing policy

Professional organisations

Professional organisations (e.g., associations of doctors, teachers, engineers) often claim specialised expertise and credibility, which can be especially influential during technical stages.

• Formulation: supply professional standards, best practices, and impact assessments

• Implementation: influence how rules interact with real-world practice (training, compliance)

• Evaluation: shape what counts as “effective” using performance measures and evidence

Social movements

Social movements use collective action to change policy by shaping public opinion, legitimacy, and urgency.

• Agenda setting: reframe issues (rights, justice, safety) to make inaction costly

• Adoption: pressure elected officials through demonstrations, coalitions, and voter mobilisation

• Implementation: keep attention on whether government action matches promises

• Evaluation: sustain salience over time, especially when outcomes are gradual or uneven

The military and national security actors

The military and related security institutions can influence policy due to their control of information, operational capacity, and perceived authority on threats.

• Agenda setting: threat assessments can prioritise security problems and funding

• Formulation: planning expertise shapes feasible options and constraints

• Adoption: influence via testimony, briefings, and defence budgeting priorities

• Implementation: operational decisions affect how policy is carried out in practice

Bureaucratic agencies: institutional power in implementation

Bureaucratic agencies have unique influence because they are positioned to translate broad laws into specific, enforceable rules.

This diagram summarizes the federal notice-and-comment rulemaking pipeline, showing how an agency drafts a proposed rule, solicits public comments, revises, and then issues a final rule. It also highlights centralized executive review (OIRA) and the downstream checks of congressional and judicial review, clarifying where different actors can intervene. Source

Even when agencies do not set the original agenda, they can strongly shape outcomes through:

• Rulemaking and guidance: specifying standards, timelines, exemptions, and reporting

• Enforcement discretion: prioritising some violations, sectors, or regions over others

• Information advantages: controlling technical details that outsiders may lack

• Feedback loops: reporting results to elected officials, affecting future decisions

Why influence varies “to varying degrees”

Influence is not equal across actors or stages; it shifts based on:

• Access: some actors regularly reach key officials; others rely on public pressure

• Resources: money, expertise, membership size, and organisational capacity

• Legitimacy: trusted expertise (professional bodies) or moral authority (movements)

• Issue type:

  • High salience issues: social movements and media attention can matter more

  • Technical issues: professional organisations and agencies tend to dominate

  • Security issues: military perspectives often carry extra weight

• Institutional venue: what works in a legislature may not work in an agency process