The growth in the popularity of owning second homes has helped fuel a property boom in parts of Britain.
A survey shows 19 new homes are needed in Nolton and Roch
But the very things which can attract prospective second-home owners - the picturesque scenery and relative tranquillity - can also put pressure on the housing market, because development is restricted.
In Pembrokeshire, where 6% of all houses are second homes - rising to 50% in some coastal areas - average property prices are now close to seven times the average wage and many local people struggle to get onto the property ladder.
One idea being considered by planners involves relaxing restrictions on land which is currently protected from development, so sites can be used for affordable homes.
Former estate agent Matthew Owens has been appointed as the county's rural housing enabler. His job is to work with town and community councils to identify demand for affordable homes and find sites where they can be developed.
"It sounds a bit dramatic but we are slowly seeing the erosion of local communities in Pembrokeshire," he said.
"Holiday homes are not the only reason - house prices have risen everywhere.
"But the communities I work with tend to be the coastal ones which would indicate that it's because they have the biggest pressure on the housing stock from the holiday market."
Although much of coast falls within Pembrokeshire Coast National Park, planners say they will look sympathetically on certain small scale developments that fall just outside the development boundaries.
"It would be land directly adjoining the current development boundary - it could not be isolated from the main settlements or dwellings," added Mr Owens.
"The houses will have a local lettings policy - there will be a qualification criteria and they will have to have a local connection to that community area either through employment or residential family link."
He acknowledges that that those buying or investing in second homes help maintain and improve properties, including derelict buildings.
And the county estimates tourism is worth between £344m and £450m annually to the area's economy - based on its research for 2004 - and that more people work in tourism in Pembrokeshire than any other industry.
However, communities which are lively and vibrant during the summer months go into virtual hibernation in the winter with shops and pubs closed and services such as buses reduced.
Surveys are being carried out in some of Pembrokeshire's most picturesque coastal communities to establish how many new homes are needed for locals.
The most recent one completed was in the community council area of Nolton and Roch.
There are only 742 people on the electoral role but the survey found that 19 new homes were needed, for people raised in the area who could not afford to live there or older residents looking to downsize.
Community council clerk Bill Hall said members were aware of a problem but surprised at the number of homes needed.
"It's an open market and anyone who wishes to buy property is entitled to do so," he said.
"The property prices have escalated quite considerably in the last couple of years and local young people are finding it very difficult to get onto the housing market.
And some believe more drastic action is needed.
Pressure group Cymuned (Welsh for communities) believes holiday homes should not account for more than 5% of any community's housing stock.
It wants VAT added to the price of second homes, council tax raised at 200% on each property and says planning permission should be required before a permanent dwelling can become a holiday home.
"Homes which are empty for a large part of the year literally create a gap in local society, which in turn makes that community less attractive for local people to live in," it said.