Fifty years ago this month, just days after the assassination of the Rev. Martin Luther King, Jr., Congress passed the landmark Fair Housing Act, making it illegal to deny housing based on a person’s skin color, religion, or country of origin.

It is altogether fitting and proper that we celebrate this milestone piece of legislation.  But we cannot yet celebrate victory.

The law changed lives, but it did not change all attitudes. It did not change all behaviors. The legacy of housing discrimination and segregation remains a reality in virtually every community in the United States.

According to the Economic Policy Institute, African-Americans have made significant advances in educational attainment, health, wealth, and wages since 1968. Yet they still lag behind white Americans in these same categories.

Even more dispiriting are data on homeownership. The African-American homeownership rate in 2015 stood at 41%, unchanged since 1968, and about 30 percentage points behind that of whites. The overall minority homeownership rate is about 47%.

An inescapable conclusion: Outlawing discrimination in housing was only a first step in achieving equality of opportunity.

Achieving the full promise of the Fair Housing Act starts with asking 3 difficult questions.

How can communities make it easier and less costly to build more housing?

Our housing system is not producing enough moderately priced homes and workforce housing. In many communities, we face critical housing supply shortages for all but the wealthiest households. The National Low Income Housing Coalition put the shortfall between the demand for housing among extremely and very low-income households and the available supply of market-rate units they could afford at 8 million units in 2015.

Can communities take steps to end the concentration of poverty?

There are a lot of interconnected economic reasons why poverty tends to concentrate in certain areas.  Unfortunately one of those reasons is a patchwork of local zoning laws, which often have the effect of restricting low-cost housing to low-opportunity neighborhoods. Many communities that are re-examining zoning laws in this light are finding that there are better ways that expand housing and growth opportunities for more people. At Fannie Mae, we have partnered with lenders to finance highly successful mixed-income multifamily communities in cities and towns across America for 30 years, and our experience tells us many more opportunities exist.

What roles do access to quality health care, employment opportunities, and education play in perpetuating housing inequality?

Many neighborhoods across America are facing more than just a lack of affordable housing options to meet demand. Often those same neighborhoods also lack access to quality schools, recreational space, jobs, healthcare, and reliable public transportation. Recognizing the multi-dimensional nature of the challenges residents in these neighborhoods face, and finding new holistic approaches that can overcome those challenges, would be a powerful blow against housing inequality.

All Americans have a stake in the answers to these questions. Community leaders, policymakers, housing advocates, and the people of my own industry, housing finance, can all bring their own perspectives to the table. Only collectively and collaboratively can we arrive at the answers.

Our American society is increasingly diverse, and will become more so with each future generation. It is time for a new conversation about housing, one that fully incorporates the holistic social, regulatory, and economic factors that have kept the promise of the Fair Housing Act from being fulfilled.

[Final Note: Like what you've read?  The author, Jeffery Hayward will be a speaker at the upcoming Building Equity event hosted by The Atlantic (which runs on April 20) and will also be available on live stream.]