Portfolio Management interview preparation

Questions

100

Traced to a firm

40

Firms

24

Updated

September 2026

Asked at

All firmsBLBlackRock4Vanguard4WMWellington Management4Amundi3ACAQR Capital Management3Neuberger Berman3SCSchroders3Man Group2MSCI2Northern Trust2AllianceBernstein1Apollo Global Management1Blackstone1BMBNY Mellon1Carlyle Group1Fidelity Investments1Goldman Sachs1Invesco1Millennium Management1MSMorgan Stanley1NUNuveen1PIMCO1SSState Street1TPTPG1

Topic

All topicsPortfolio theory5Factor models8Asset allocation11Rebalancing3Portfolio construction7Benchmarks and tracking error5Performance measurement8Risk management6Fixed income and LDI5Currency and global3Implementation and costs5Active versus passive6India markets7Brainteasers5Career and fit16

Level

AnyCoreIntermediateHard

Type

AnyTechnicalCaseMarket viewFitBrainteaser

1. 067Make the arithmetic case for passive investing.Active versus passiveIntermediatetechnicalAsset managementWealth management

   Say this

   Sharpe's arithmetic: before costs, the average actively managed dollar must earn exactly the market return, because active investors collectively hold the market. After costs, the average active dollar must underperform by the amount of those costs. It is an identity, not an empirical claim.

   Then walk it

   1. The logic in one step: the market is the sum of all holdings. Passive holders earn the market minus a few basis points. So the remaining, active, holdings must also earn the market gross, which means active as a group underperforms by its fee and cost load.
   2. Put the numbers on it. A 75 basis point active fee plus 30 basis points of trading cost against an index fund at 5 basis points is a 100 basis point annual handicap. Compounded over 30 years that is roughly a quarter of the terminal wealth.
   3. The evidence lines up with the arithmetic. SPIVA and Morningstar's active-passive barometer consistently show 70 to 90 percent of active funds trailing their benchmark over 10 to 15 year periods, and the survivors are partly a survivorship artefact because the worst funds close.
   4. Persistence is the second nail. Top quartile managers in one five-year period are close to randomly distributed in the next, so even if skill exists, identifying it in advance is a separate and much harder problem than establishing that it exists.
   5. The rebuttals worth knowing and conceding: the arithmetic is about the average dollar, not every dollar, so it does not prove no manager can win. It says the average client cannot, which is the relevant fact for an adviser. And it is silent on less efficient markets, smaller markets and asset classes where the index is poorly constructed.
   6. So the professional conclusion is a barbell: index the efficient, liquid core where the arithmetic is hardest to beat, and spend the fee budget only where dispersion is wide and there is a structural reason for an edge. That is what most large institutions have converged on.

   Where candidates lose it

   Arguing it purely from performance statistics. The statistics can be disputed, dataset by dataset; the arithmetic cannot. Lead with Sharpe's identity, then support it with SPIVA. And concede the limit of the argument, that it is about the average dollar, or you will sound like an ideologue rather than an analyst.

   Expect next

   • So where would you still pay for active?
   • What happens if everyone indexes?
   • Does the arithmetic hold in small cap India?
2. 068What is the difference between an ETF and a mutual fund?Active versus passiveCorephone / first roundVanguardGeneralist · Malvern · 2026

   Say this

   Both are pooled vehicles, but an ETF trades on an exchange all day at a market price while a mutual fund transacts once a day at NAV. The structural consequence that matters is the creation and redemption mechanism, which makes ETFs more tax efficient and shifts trading costs onto the person doing the trading.

   Then walk it

   1. Dealing: mutual fund orders are aggregated and struck at one NAV per day. An ETF trades continuously at a price that can sit at a premium or discount, with an authorised participant arbitraging the gap by creating or redeeming baskets.
   2. The in-kind mechanism is the real difference. Redemptions are met by delivering securities to the authorised participant rather than selling them, so the fund does not realise capital gains. In the US that makes ETFs materially more tax efficient than mutual funds, which must distribute realised gains.
   3. Cost incidence: in a mutual fund, one investor's redemption forces the fund to trade and all remaining holders pay the cost. In an ETF, the seller crosses the spread themselves, so long-term holders are insulated. That is a genuine fairness advantage.
   4. Where mutual funds are better: automatic investment plans and fractional amounts, no bid-offer spread for regular small contributions, and no risk of trading at a discount in a stressed market. For a monthly SIP investor a mutual fund is often the better instrument even if the ETF's expense ratio is lower.
   5. In India the differences are sharper. ETF liquidity is thin outside the Nifty and Sensex trackers, so tracking difference and impact cost can exceed the expense ratio saving, and index funds rather than ETFs are usually the better passive vehicle for a retail investor. Institutional flows, particularly EPFO, dominate Indian ETF assets.
   6. And the caveat on stressed markets: an ETF's price is a real-time price, so in a dislocation it can trade well below the stale NAV of an illiquid bond portfolio. That is the ETF telling the truth faster, not the ETF failing, and it is worth being able to say that clearly.

   Where candidates lose it

   Answering only 'ETFs trade intraday'. The substance is the in-kind creation and redemption mechanism and who bears trading costs. And do not claim ETFs are always better; for a regular small contribution plan, and in India where ETF liquidity is thin, an index fund is frequently the right answer.

   Expect next

   • Why is an ETF more tax efficient?
   • What happens when an ETF trades at a discount to NAV?
   • ETF or index fund for an Indian retail investor?

   Reported by candidates at Vanguard (Generalist, Malvern, 2026). Source: Wall Street Oasis.

3. 070Where is active management still worth paying for?Active versus passiveIntermediatetechnicalAsset managementInstitutional asset management

   Say this

   Where dispersion is wide, information is costly, the index is badly constructed, or the market has a structural constraint you can exploit. Small caps, emerging and frontier markets, credit, private markets, and anything where the benchmark itself is a poor portfolio.

   Then walk it

   1. The general test is cross-sectional dispersion. If the gap between the best and worst stock in a market is 10 percentage points, skill cannot earn much; if it is 60, the same skill is worth far more. That is why small caps and emerging markets pay better for research.
   2. Second test, index quality. Cap-weighted bond indices weight by amount of debt issued, so you mechanically own more of the most indebted issuers. Active credit management starts with an advantage that has nothing to do with skill.
   3. Third test, structural constraints on other investors. Forced sellers on a downgrade, index funds having to trade at reconstitution, insurance and bank capital rules pushing assets out. Those are persistent and they are not arbitraged away because the constraint is real.
   4. Fourth, where beta is not available cheaply. You cannot index private credit, infrastructure or catastrophe reinsurance, so the only access is active, and the relevant question becomes manager dispersion rather than active versus passive.
   5. And the reverse, where I would never pay: developed large cap equity core, government bonds, and any mandate where the manager's tracking error is under 2 percent. The arithmetic there is close to unbeatable and the fee is a certainty while the alpha is not.
   6. So the practical construction is a barbell: index the core cheaply, concentrate the fee budget in high active share, high dispersion, capacity-constrained strategies, and negotiate fees that only pay for the residual after factor exposures. That last point matters, because much of what is sold as active is factor beta with a fee on top.

   Where candidates lose it

   Giving a list of asset classes with no organising principle. The principle is dispersion plus information cost plus index quality plus structural constraints, and being willing to name where you would refuse to pay, developed large cap core, makes the answer credible rather than diplomatic.

   Expect next

   • Why are cap-weighted bond indices badly constructed?
   • How would you structure the fee for an active mandate?
   • Is Indian large cap efficient enough to index?
4. 072Is ESG investing a constraint or an edge? What does the evidence actually say?Active versus passiveHardsuperdaySustainable investingAsset management

   Say this

   Mostly a constraint with some genuine risk information inside it. Exclusion shrinks the opportunity set and costs tracking error. Governance quality and, increasingly, transition risk carry real financial information. Claims of a reliable ESG return premium do not survive factor adjustment.

   Then walk it

   1. The strongest part of the evidence is governance. Poor governance, related party transactions, a dominant shareholder extracting value, weak board independence, is associated with worse outcomes, and in India that is a first-order stock-specific risk rather than an ethical preference.
   2. The environmental side is mostly a valuation and timing question. Carbon pricing, stranded asset risk and regulation are cash flow effects that belong in the model. Whether the market has already priced them is the empirical question, and the answer varies by sector and by year.
   3. The performance record: ESG funds outperformed in 2019 to 2020 and underperformed in 2022, and both were driven by their sector and factor tilts, underweight energy, overweight growth and quality. Once you control for those exposures, the ESG alpha is close to zero. So the honest statement is that it is a factor tilt with a label.
   4. There is also a theoretical reason to expect a lower return, not a higher one. If investors prefer green assets for non-financial reasons, they bid the price up, which lowers the expected return. Pastor, Stambaugh and Taylor make exactly that argument: you should expect to pay for your preferences.
   5. Where it is genuinely an edge: as extra data. Employee turnover, safety records, regulatory fines and emissions intensity are leading indicators of operational quality, and they are underused because they are unstructured. That is a research advantage, not an ESG position.
   6. So my position is to integrate the material data into the fundamental view, be transparent about the tracking error any exclusion causes, avoid composite vendor scores because providers disagree, and never sell a client a return premium that the evidence does not support. Greenwashing risk is now a regulatory risk as well as a reputational one.

   Where candidates lose it

   Picking a side ideologically. Both 'ESG is marketing' and 'ESG generates alpha' are weak answers. The credible version separates governance evidence from environmental timing, explains that historical ESG outperformance was a factor tilt, and knows the theoretical argument that popular green assets should have lower expected returns.

   Expect next

   • So why did ESG funds do badly in 2022?
   • Would you expect a green asset to return more or less?
   • How would you use ESG data as a research input rather than a screen?

Firm tags come from public, anonymous candidate reports on Wall Street Oasis: strong signal, not sworn testimony. Firms are named as the places a question was reported, not as partners of Fin Maverick. Answers are written for this page to show how to think out loud; they are not scripts to recite.