ESG investing is not one strategy. Investors can use environmental, social and governance information in several different ways, from excluding particular industries to selecting companies with stronger ESG characteristics, integrating ESG factors into fundamental research or actively engaging with management. The right approach depends on the investor's objectives, risk tolerance and definition of sustainability.

What Is an ESG Investment Strategy?

An ESG strategy incorporates environmental, social and governance considerations into security selection, portfolio construction or ownership decisions. The process can be simple, such as excluding companies involved in specific activities, or much more integrated, with ESG factors forming part of a broader financial assessment.

The label alone does not tell investors which approach a fund uses. Two products marketed as ESG can have very different holdings, benchmarks, turnover and risk characteristics. Reading the methodology is therefore more important than relying on the product name.

The Main ESG Investing Strategies

1. Exclusionary or Negative Screening

Exclusionary strategies remove companies or activities that conflict with predefined criteria. Common screens can relate to fossil fuels, tobacco, weapons, gambling or other areas that investors choose to avoid.

The approach is transparent and can make a portfolio closely aligned with an investor's values. The trade-off is that exclusions can reduce diversification and create larger exposures to the sectors that remain. Investors should therefore examine how screening changes sector weights and benchmark-relative risk.

2. Best-in-Class Investing

Best-in-class strategies compare companies with their industry peers and favour those that score more strongly on selected ESG measures. This allows a portfolio to retain exposure to sectors that an exclusion-only approach might remove entirely.

Investors should understand whether the strategy rewards absolute performance or relative performance. A company can rank highly within an environmentally intensive industry while still having a large absolute environmental footprint. The methodology needs to match the investor's actual objective.

3. ESG Integration

ESG integration incorporates financially material ESG considerations into traditional investment research. A fund manager may assess governance, labour practices, regulatory exposure, resource dependency or climate-related risks alongside revenue, margins and valuation.

This approach can be useful because it connects ESG information directly to financial outcomes. The key diligence question is whether ESG genuinely changes security analysis or simply appears in reporting after the investment decision has already been made.

4. Thematic ESG Investing

Thematic strategies focus on a particular sustainability-related opportunity, such as renewable energy, electrification, water infrastructure, energy efficiency or resource management.

The attraction is clear: the investor gains targeted exposure to a structural theme. The risk is concentration. A thematic fund may hold many securities while remaining heavily dependent on one industry, technology or regulatory trend. Valuation risk can also become significant when a theme attracts substantial investor enthusiasm.

5. Shareholder Engagement and Active Ownership

Engagement strategies seek to influence companies through voting, dialogue with management, shareholder resolutions or escalation when progress is inadequate. The investor may retain a company in the portfolio while seeking improvements in governance, environmental performance or social practices.

Engagement can take time and its success depends on the investor's influence, the company's willingness to change and the quality of the engagement process. Investors should therefore look for evidence of objectives, milestones, voting policies and outcomes rather than assuming that an “active ownership” label guarantees impact.

6. Combining ESG Strategies

Many portfolios combine several methods. A manager might exclude selected activities, integrate ESG factors into fundamental research and engage with the companies that remain eligible. Combining approaches can create a more nuanced process, but it also makes it more important to understand the hierarchy of decisions.

Ask which rule comes first. Does an exclusion automatically remove a company? Can a strong ESG improvement change its status? How are trade-offs between environmental, social and governance considerations resolved? Clear answers make a strategy easier to evaluate.

ESG Strategies and Portfolio Risk

Changing the investable universe can change portfolio risk even when the objective is non-financial. Exclusions can increase sector concentration, thematic strategies can increase factor exposure and best-in-class approaches can produce different country or industry weights from a conventional benchmark.

Investors should therefore compare volatility, drawdown, correlation and concentration in addition to ESG metrics. Diversification analysis can help identify whether an ESG strategy has introduced unintended overlap or dependence on a small number of economic drivers.

How to Compare ESG Funds

• Objective: What sustainability outcome is the strategy trying to achieve?
• Methodology: How are ESG factors defined, weighted and applied?
• Holdings: What companies and sectors are actually in the portfolio?
• Benchmark: How different is the portfolio from a conventional market index?
• Engagement: What voting and stewardship activities are undertaken?
• Costs: What fees, turnover and implementation expenses apply?
• Risk: How do volatility, drawdown and concentration compare with alternatives?

ESG Strategy vs ESG Rating

An ESG rating describes an assessment of a company or fund, while an ESG strategy describes how investments are actually selected and managed. A highly rated company is not automatically suitable for every ESG portfolio, and a portfolio with a high average rating may still have large exposures to particular sectors or factors.

This distinction is important when comparing funds. Review the rules that create the portfolio rather than assuming that the highest aggregate score represents the strongest strategy.

How to Evaluate Performance

Performance should be compared with the appropriate benchmark and with the risks taken to achieve the result. A strategy may underperform because it excludes a strong-performing sector, or outperform because it has a favourable growth or quality tilt.

Investors should therefore ask whether returns came from ESG characteristics, conventional investment factors or simple changes in sector and country weights. Our guide to the drawbacks of ESG investing explores why these differences matter.

FAQ

What is the simplest ESG strategy?

Exclusionary screening is usually the simplest because the rules can be clearly defined. More integrated strategies require greater judgement about materiality and trade-offs.

Is thematic investing the same as ESG investing?

No. A thematic strategy targets a specific investment theme. It can be ESG-related, but not every thematic investment strategy is designed around ESG objectives.

What is ESG integration?

ESG integration means incorporating financially material environmental, social and governance factors into investment analysis alongside conventional financial information.

Can ESG investing increase portfolio risk?

Yes. Screening or thematic choices can increase sector, country or factor concentration. The result depends on the specific strategy and portfolio construction.

Related Reading

Continue exploring this topic with our ESG investing explained, ESG vs SRI vs impact investing and drawbacks of ESG investing.

Conclusion

ESG investing encompasses several distinct approaches rather than one standard method. Exclusions, best-in-class selection, ESG integration, thematic investing and shareholder engagement each solve a different problem and create different portfolio trade-offs. The best strategy is the one whose objectives, methodology and holdings are clear and whose risk profile fits the investor's broader portfolio. Understanding how the strategy actually works is more useful than choosing an investment simply because it carries an ESG label.