Plain-language explanation.
Public finance studies how governments raise revenue through taxes and allocate spending on public services, transfers, and public goods. It examines the economic effects of taxation, the sustainability of public debt, and the equity-efficiency trade-offs in fiscal policy.
Core concepts and standard treatment.
Core public finance covers taxation theory (optimal taxation — Ramsey rule — inverse elasticity rule — tax inelastic goods more; Mirrlees income tax — optimal schedule — trade-off between efficiency and redistribution; Laffer curve — revenue maximising tax rate — Diamond and Saez empirical estimate of top rate 70%; tax incidence — burden of tax depends on elasticities not legal liability — VAT regressive in isolation; Pigou tax — correcting externalities — carbon tax — Stern Review; Harberger triangle — deadweight loss of taxation — excess burden), public spending (public goods — non-excludable, non-rival — market provision fails — free-rider — Samuelson condition; merit goods — positive externalities — health, education; welfare state functions — social insurance — Beveridge five giants — want, disease, ignorance, squalor, idleness; public expenditure frameworks — PESA — public expenditure statistical analysis — HMT — RDEL, CDEL, AME), and fiscal policy (automatic stabilisers — tax revenue falls and benefits rise in recessions; discretionary fiscal policy — fiscal multiplier — Blanchard and Leigh; Ricardian equivalence — Barro — fiscal expansion offset by savings for future taxes; fiscal sustainability — debt-to-GDP ratio dynamics — r-g dynamics; fiscal rules — UK debt rule — cyclically adjusted primary balance; IMF fiscal monitor — structural balance).
Deeper theory, debates and edge cases.
Advanced public finance covers tax policy design (UK tax system — income tax — personal allowance — higher rate threshold — 20% basic, 40% higher, 45% additional; NICs reform — employer NICs — OBR costings; capital gains tax — entrepreneur's relief — BADR; IHT — residential nil rate band; corporation tax — full expensing — R&D tax credits reform — HMRC; VAT — standard 20% — reduced and zero rated — fiscal neutrality; stamp duty land tax — residential vs commercial; Council Tax — 1991 bands — revaluation debate — IFS), public debt management (UK Debt Management Office — gilts — conventional and index-linked — Green Gilts — OBR debt projections — debt sustainability; Japan high debt — JGB market; EU Stability and Growth Pact — 60% debt to GDP; debt relief — Paris Club — HIPC initiative — MDRI — multilateral debt relief; debt transparency — IIF — DSSI — Debt Service Suspension Initiative — G20 Common Framework), and intergovernmental fiscal relations (fiscal federalism — Oates — decentralisation theorem; Tiebout model — voting with your feet; UK fiscal devolution — Barnett formula — block grant — Scottish income tax; business rates retention — MHCLG; fiscal equalisation — German Laender system — Finanzausgleich; EU own resources — MFF — VAT and GNI contributions; OBR devolved tax forecasting — HMRC clearances).
How it is applied in practice.
At the Treasury official and fiscal policy adviser level, practitioners contribute to National Tax Journal and Fiscal Studies; advise on UK tax and spending (OBR — fiscal forecasting — FSR — Fiscal Sustainability Report; HMT Green Book — CBA for public projects — Aqua Book — analytical quality; HMRC — Tax Gap — tax avoidance — GAAR; NAO — VFM studies — public accounts scrutiny; IFS analysis — Budget commentary — micro-simulation of tax changes — TAXBEN model); lead international tax cooperation (OECD Pillar 1 and 2 — global minimum tax — 15% GMT — BEPS 2.0 — qualified domestic minimum top-up tax — QDMTT; OECD CbCR — country-by-country reporting; FATF — financial action task force — AML — anti-money laundering; EU ATAD — Anti-Tax Avoidance Directive; digital services tax — DCIT — UK DST 2% of revenues); design social security and benefits policy (Universal Credit — DWP — assessment period — taper rate — work allowance; UC marginal tax rate interaction with income tax; auto-enrolment pensions — NEST; Pension Credit — retirement poverty; IFS Deaton Review — inequalities and public policy); and advise local government (Section 114 notice — Section 25 CA2003; business rates appeals — VOA; Council Tax Support — CTS — localisation); and contribute to climate fiscal policy (carbon pricing — UK ETS — pot 1 allocation; carbon taxes — Stern-Stiglitz High-Level Commission — $50-100/tonne CO2 by 2030; TCFD mandatory reporting — UK — SDR — sustainable disclosure requirements).