The converted Holiday Inn at 4640 Main Street is packed, but fulfilling its purpose. The nonprofit facility now houses 280 veterans with head injuries, mental illness or other combat-related wounds.

The only hitch: Most are Vietnam veterans. Houston so far has barely glimpsed the psychological harm suffered by thousands of soldiers soon to come home from Afghanistan and Iraq.

It's a certainty, though, that they will need services far beyond what Houston currently can give.

"We're basically busting at the seams, to tell you the truth, " said Tom Mitchell, director of the Main Street facility. "And it may be three, or four, or five years before (new) veterans start hitting the streets" because post-traumatic stress disorder or traumatic brain injuries unglued their lives.

In some ways, these newer veterans will benefit from lessons of the Vietnam War and, more recently, scandalous mistreatment at Walter Reed Army Medical Center.

Doctors today are more familiar with PTSD. Its symptoms include anxiety, insomnia, substance abuse and depression. And the Walter Reed revelations goaded Congress into studying veterans' physical and psychological needs and better coordinating the Veterans Administration and Defense Department so wounded veterans can get treatment more easily.

Even so, both national and local mental health experts say programs aren't in place to handle the flood of homecoming soldiers who will be suffering PTSD and traumatic brain injury. It's estimated that 17 percent to 30 percent of soldiers will come home with PTSD alone.

Harris County, with its gross deficit in mental health care services for civilians, could be particularly hard hit. Already, about 70 percent of Houston's 10,000 homeless people suffer serious mental illness. Some 30 percent of those homeless are veterans, mostly from Vietnam.

The returning soldiers from Iraq and Afghanistan could have even more severe problems. The new phenomenon of repeated, prolonged combat — two, three, even four tours of duty — intensifies traumatic stress disorders.

Houston will see a large number of these patients. One in 11 soldiers who are wounded in Iraq and Afghanistan is a Texan. And 25 percent of the state population is from the Houston-Galveston area.

To their credit, Mayor Bill White and County Judge Ed Emmett began tackling this complex problem last summer. At a summit of military and community leaders, they asked teams to design the healthiest possible veterans' policies.

Some of that planning is now bearing fruit. The city offers a database for veterans to get all the services they've earned at www.houstontx.gov/vetaffairs/index.html.

Perhaps uniquely, Houston also has hired a full-time veterans affairs director, Buddy Gratham. Meanwhile, advocates are working with sociologist Stephen Klineberg on a survey they will mail to veterans returning to this area so they can state their needs.

Finally, the Greater Houston Mental Health Association is studying federal resources for veterans; in a month, president Betsy Schwartz said, the group can report the biggest gaps in federal funding. It can also guide nonprofits in how to maximize what's there.

Some tactics, however, are already clear. First, veterans will need lifetime access to PTSD diagnosis and care. The symptoms can years take to surface, and when they do they can be devastating. Typically, acute sufferers drive off the very loved ones they need to get better. That's when PTSD's full effects appear: job loss, substance abuse, homelessness, criminal behavior.

Second, preventive treatment needs to include veterans' families. A San Antonio group has just launched a $100,000 pilot program to veterans and their loved ones.

This is the model to which Houston ought to aspire. If it sounds costly, the public cost of homelessness, emergency room visits and criminal justice is far greater.

Finally, Houston needs, as often as possible, to offer veterans peer-to-peer counseling. There are strong biases against mental health care in the military, where even natural stress reactions are seen as weakness that threatens the "team."

For that reason, many homecoming soldiers don't seek the mental health care they need and have earned. Peer counseling counters that problem.

These are ambitious but critical goals. "Let me tell you my theory about PTSD," said US VET's Mitchell, a Vietnam veteran and licensed counselor. "Everyone that is in a combat zone experiences PTSD. The key is what support systems are there for when they get home."