Mid Cap is a painless way to round out core large cap holdings, with modest diversification benefits.

Small cap indexes represent 8-16% of the total US stock market. Many investors have no small cap exposure. Is this wise?

Large cap ETFs are relatively similar, but minute differences are amplified by huge portfolio allocations.

In the last six months emerging market ETFs have struggled. Is the period of strong growth on low inflation over?

Value and growth acted unexpectedly throughout this cycle.

Commodity ETFs are among the most popular and successful funds in the market today. They are best used strategically.

Turmoil, inflation and natural disasters make country ETFs challenging and potentially lucrative.

The rabbit is running. Growth ETFs outperforming value.

Technology ETFs outperformed for three years, but have paused at last.

Agricultural ETFs track the price of agricultural commodities. How have they performed recently?

China slowing down and encountering inflation but less volatile and less correlated with the US.

Utilities ETFs provide diversity in the face of Japan's nuclear disaster.

Market cap weighting may not be the best way to index. Fundamental financial measures are finding support in historical data and investor acceptance.

Are U.S. treasury bonds and treasury bond ETFs safe? Is the price for safety too high?

Equal weighted ETFs diversify, but they may not lower volatility.

ETFs tracking markets in oil-rich countries used to be a bet on oil. Have recent political events in the Middle East changed this?

Most commodities ETFs roll futures contracts frequently, at huge cost to their investors.

Specialty ETFs are strategy-based funds designed to beat the market benchmark. Are they worth it?

REIT ETFs are soaring on improved but not yet stellar fundamentals.

After two decades of stagnation, investors are ignoring Japan. Is this complacency justified?

Total market ETFs are useful not just as easy buy-and-hold tools but as benchmarks to beat.

Latin American ETFs are moving up on expanding Chinese demand for natural resurces, inflation-proof assets and dollar diversification.

Financials are not driving the market quite the way they were two years ago. Volatility remains but at nowhere near the same level.

In 2010, precious metals ETFs were some of the market's best performers. Base metals ETFs stagnated. What's ahead for metals ETFs in 2011?

Europe is seemingly threatened as rarely before but investors are hanging on for ride.

In the past month, US treasury ETFs have sold despite aggressive buying from the Federal Reserve. What's ahead for international fixed income ETFs?

Dividend ETFs were too full of financial stocks to be defensive in recent years, but that has changed and they now play a more traditional role.

Can ethics and values be profitable? Socially responsible ETFs select companies based on political, social, environmental and corporate governance considerations.

Munis dipped again. Is volatility here to stay?

Is manufacturing growth strong enough to support further outperformance of materials ETFs?

Politicians target health care but will they follow through?

It is the best of times for corporate bond issuers. It's a pretty good time for corporate bond ETF investors too. But investors should avoid the temptation to buy investment gr

Telecom is recovering faster than most sectors, but is still moderaly priced.

The worlds fastest growing economies are in Asia. ETFs tracking the Asian markets offer exposure.

Industrials have led the market out of the recession, and now exports are being boosted by a low dollar.

Energy Sector ETFs are underperforming broad market benchmarks. Is this a temporary phenomenon or a structural trend?

Exchange-Traded Notes serve niche areas with flexibility at a price

Are high yield bond ETFs expensive right now, or cheap? The answer depends on investors' bond default expectations.

Mid-sized US companies remain a useful tool for investing by company size.

When people are 'just getting by,' consumer staples ETFs make attractive investments.

Currency ETFs are the best way to play currency shifts, especially Dollar weakness.

After a strong run in 2009 and 2010, consumer discretionary ETFs look pricey.

Frontier markets deliver the wild ride emerging markets used to.

Small cap ETFs have outperformed their large cap brethren for a decade. Can the trend continue?

International ETFs are the obvious complement to US large cap, although now is not the most propritious time to venture abroad.

Emerging market economies are growing much faster than developed economies. Are emerging market ETFs worth the risk?

Large cap ETFs get huge amounts of assets but little reflection.

Lately, commodities and commodity ETFs seem to be adding to portfolio volatility rather than reducing it.