Many might assume these uninsured veterans could simply get their insurance through the Department of Veterans Affairs, but only two-thirds of veterans are eligible for VA health care. Some veterans make too much money to qualify for VA health care and some were discharged from the military under other than honorable conditions. In any case, health care provided through the Veterans Health Administration is unlike most private insurance plans even though enrollment will satisfy mandatory coverage under the Affordable Care Act. Notably, veterans’ families are not usually covered by VA health care the way they would be with private insurance or Medicaid.

While veterans who do not qualify for VA health care might qualify for Medicaid with the expanded eligibility laid out in the ACA, at least 23 states will not offer it after the Supreme Court ruled compulsory Medicaid expansion unconstitutional. That leaves over a quarter of a million veterans and their families without access to health care through Medicaid.

Of course, plenty of veterans will change how they use health care services as these new regulations go into effect. VA expects a net increase of 66,000 veterans to enroll in health care, though lawmakers have questioned the accuracy of these estimates and the assumptions on which they are based. For example, Rep. Dan BenishekDaniel (Dan) Joseph BenishekRepublican groups launch final ad blitz in key House battlegrounds Tea Party class reassesses record Michigan Republican to retire MORE (R-Mich.) questions whether any veteran would choose Medicaid over VA services. But if VA is only requesting funding to cover 66,000 new enrollees, the agency could find itself struggling to meet an increased demand for health care.

New health insurance exchanges, too, could draw some veterans out of the VA system and onto private health insurance plans. But this raises concerns among those like Kenneth Kizer, former head of the Veterans Health Administration, who says that by creating so many options for veterans, the new law risks a fragmentation of services. Writing last year in the Journal of the American Medical Association, Kizer noted that some studies show veterans who receive a combination of VA and non-VA care “are more likely to be hospitalized and to die within a year compared to VA-only users.” Veterans are also more likely to be adversely affected by fragmented care because non-VA health care providers are not as familiar with ailments more common among veterans such as PTSD.

All of this suggests the need for much better coordination of veterans’ health care across not only VA but also non-VA providers such as Medicare and private insurers. Without proper coordination, doctors may prescribe drugs with deadly interactions, repeat unnecessary tests, or misdiagnose serious illnesses. For this reason the USC Center for Innovation and Research on Veterans and Military Families recently encouraged “professional medical and health-care organizations to communicate with their service delivery members regarding evidence-based healthcare protocols that address veterans and military families.” This also raises some very important questions about how we currently care for our veterans and how we plan to ensure they have the best care available in the future—but those questions have yet to be answered.

The Affordable Care Act will have a significant impact on the way veterans access health care. In order to mitigate any negative consequences on veterans’ health, we must start looking at solutions now, before it is too late.

Frank is a Navy veteran and CEO of Virginia-based VetAdvisor®.