DALLAS >> Big 12 Commissioner Bob Bowlsby said today there is “unanimity” among leaders from five power conferences that significant changes are needed now in the NCAA.

“We all have a sense that transformative change is going to have to happen,” Bowlsby said at the start of the Big 12’s football media days. “This is not a time when trimming around the edges is going to make very much difference.”

Bowlsby and the commissioners of the SEC, Big Ten, Pac 12 and ACC met about six weeks ago to discuss issues, including an NCAA legislative system that makes it difficult to enact substantial changes or enforce the rules in place. There are also huge gaps in resources between schools in the same divisions.

SEC Commissioner Mike Slive, whose league has won the last seven national titles in football, delivered a similar message last week at his league’s media days.

“It’s bad grammar but a good concept: If we always do what we’ve always done, we’ll always get what we’ve always got,” Bowlsby said. “That’s kind of where we are right now.”

ACC Commissioner John Swofford also addressed the issue Monday, saying significant changes could be put in place when the NCAA has its annual convention in January. Bowlsby even indicated the possibility of a special convention.

Before taking over as the Big 12 commissioner just more than a year ago, Bowlsby had been a long-time athletic director — serving at Stanford, Iowa and Northern Iowa. Bowlsby said his thoughts about the NCAA are “driven by frustration more than anything else. And that’s been a frustration that’s grown over the last 15 years.”

A real consideration could be a separate division for the top football-playing schools, for which Bowlsby said he is listening and learning about many different models.

Therein lies what can become another difficult issue: determining who would be part of such a division.

“If you begin trying to put together homogeneous groups, somebody gets included, and somebody gets left out. … Wherever you draw those lines, if they’re bright lines, you have controversy,” he said. “I’m pretty dyed in the wool of the NCAA, and I believe with all my heart that a solution inside the organization is the right one. Whether Division IV is the right one, the devil’s in the details.”

Among other possible changes Bowlsby suggested was to consider segregation by “size and scope” or maybe by sport.

“There are about 75 schools that win 90 percent of the championships in the NCAA, and we have a whole bunch of others that don’t look much like the people in our league, but yet through rule variation they’re trying to compete with us,” Bowlsby said.

Bowlsby said it has become too easy for schools to get into Division I — and too easy to stay there.

“There are programs that have $3 million budgets and programs that have $160 million budgets. How do you begin to try and do things that are good for one that are also good for the other?” he said. “I don’t know how you go about solving problems other than get like-minded people together and trying to come up with a solution.”

On the idea of federation by sport, Bowlsby said, “it’s probably unrealistic to think that we can manage football and field hockey by the same set of rules. I think some kind of reconfiguration of how we govern is in order.”

Even with all the issues and the difficulty so far in trying to solve them, Bowlsby said he has not heard anyone talking about seceding from the NCAA. He could see that as a legitimate threat only “as a last resort.”

Bowlsby said he was not being critical of NCAA President Mark Emmert, but rather “critical of an organization that’s just not very efficient.” Bowlsby described it as organization with very broad-ranging responsibility and oversight, one in which he believes commissioners and athletic directors should have more involvement in developing the agenda.

“We need to think a little bit about reevaluating our core purpose,” Bowlsby said. “I’m not sure we’re doing as good a job with some of the core competencies as we need do. And perhaps a narrower focus would help.”