Headteachers are calling for cash to be set aside to meet their training needs, amid concerns that they are getting a poor deal compared to colleagues in England.
The National Association of Head Teachers Cymru claims the Assembly government has not identified funding for training for experienced heads in its Better Schools Fund grants to councils for the past two years.
And it says heads are missing out on valuable networking opportunities because of the lack of facilities in Wales compared with England - which has the National College for School Leadership, based in Nottingham.
Iwan Guy, NAHT Cymru's acting director, said the only nationally funded training programmes in Wales are the National Professional Qualification for Headship (NPQH) for people aspiring to be heads, and the professional headship induction programme for first-time appointments.
But there is nothing for experienced heads as a third programme - the leadership programme for serving heads (LPSH) has been frozen and will not recruit again until 2007.
Mr Guy said: "There is nothing for existing heads who are not new to the job. Heads know, no matter how long they have been in post, that they do need refreshing.
"At a time when there are so many initiatives landing on their desks, heads are being left to 'get on with it'. This is not good enough. They are encouraging their own staff to go on career development, but they need in-service training too."
He added: "We would like to see some form of school leadership college established in Wales. It doesn't have to be a brick building, it could be online. It's not often we look over the border with envy, but this time we do."
The NCSL - a "Sandhurst for heads" - opened in 2000, and manages national programmes such as NPQH and LPSH, as well as running a wide range of additional training courses, programmes, online communities, and school networks.
Sue O'Halloran, head of Garth primary school, Maesteg, Bridgend, is one of those who wants to see an online college in Wales.
She said: "I have done NPQH, induction and LPSH, and I'm only in my fifth year of headship. Where do I go now? Do I know everything I need to know about being a head? I don't think so."
As a first-time head, Miss O'Halloran, 44, was a member of the pilot pen i ben (head to head) online network, set up in 2001 for new school leaders to share their experiences and problems. It closed down in 2003 when Assembly government funding dried up.
"I was quite bereft for a while because I was so used to going on-line and talking to colleagues across south Wales," said Miss O'Halloran. "It would be great if it could be extended to all heads. We exchanged policies and good practice, and got to know each other."
An Assembly government spokeswoman said it was "exploring opportunities to give online provision for the profession".
Funding for headship training was removed from the Better Schools Fund in April 2005 and put directly into the centrally funded pound;1.55m national headship development programme for Wales, she added.
Following a review of the programme, it is due to be relaunched in 2007 - as is the LPSH. There are also plans for new leadership seminars for experienced school leaders, to be delivered by their contemporaries.
Up to 300 heads a year will be able to access the fully-funded seminars from September.