During a Center for American Progress seminar on Monday, a former top Obama administration official charged with developing Obamacare said the shift to the president’s healthcare overhaul will be “messy” and fraught with “unanticipated” challenges.

“We know it’s going to be messy,” said Jeffrey Crowley. “There are going to be things that come up that are unanticipated.”

The panel discussion centered on how Obamacare will affect HIV/AIDS and the lesbian, gay, bisexual and transgender community. “If we do everything we can possibly think of, it’s still going to be a messy transition, but we’ll end up in a better place,” said Crowley.

National Minority AIDS Council Director of Legislative and Public Affairs Kali Lindsey agreed. “One of the realities of the Affordable Care Act is that everything is not going to be perfect when it’s implemented on day one.”

The seminar also touched on how illegal immigrants, who are not supposed to be eligible for Obamacare, will be affected by the new law.

Health and Human Services Public Health Policy Director Mayra Alvarez said public health advocates should pay close attention to how the passage of the much-discussed comprehensive immigrant reform package deals with healthcare.

“Let’s keep our eyes on the prize of comprehensive immigration reform,” she Alvarez. “I just want to emphasize that the undocumented are part of our communities. They are part of the people that many of our organizations serve. They go to school with our children, they work with us. And I think first and foremost the administration is committed to passing comprehensive immigration reform…”

Obamacare’s full implementation is slated to begin in 10 months.