Author JK Rowling has urged politicians to end the "neglect" of multiple sclerosis sufferers in Scotland.
JK Rowling is the patron of the MS Society Scotland
The patron of the MS Society Scotland was among more than 200 people who lobbied the Scottish Parliament.
Campaigners want the Scottish Executive to set a national standard of care which would have to be met by every health board in the country.
Ms Rowling, whose late mother was diagnosed with the disease, stressed the importance of such a step for sufferers.
"It is simply inhumane to neglect people because they have an inconvenient illness that won't go away," said the Harry Potter author.
"We live in the MS capital of the world; Scotland ought to be leading the world in this area, not falling lamentably short.
"People's lives are being blighted, just as my mother's was, not only by this cruelly unpredictable illness, but also by the inadequacy of their care."
Scotland has one of the world's highest rates of multiple sclerosis, yet sufferers say they are supported more by charity than by the NHS.
MS is an incurable disease of the central nervous system, which impairs muscle control and usually worsens over time.
According to recent research, many Scots believe their quality of care depends on where they live.
Fewer than a third of Scots said they could always access MS services on the
NHS when they needed them.
Nine out of 10 surveyed in Scotland said care
should be better coordinated.
The MS Society is calling on the Scottish Parliament to introduce a basic standard of care across the country.
Mark Hazelwood, the director of MS Society Scotland, said that six of Scotland's 15 health boards have no MS nurse or other specialist.
"The Scottish Executive should set a standard that spells out the basics which everyone ought to get, wherever they live," he said.
"We're not asking for the moon. Such standards are due to be published in England and Wales this month, but in Scotland there is nothing, even though we have the highest rate of MS in the world."
Convener of Holyrood's health committee Christine Grahame said: "The committee is very concerned about postcode delivery of treatment for MS sufferers.
"We intend to do an inquiry into recruitment and retention of staff because there is a huge issue about there not being sufficient staff."
She said that the committee had pushed the executive over provision of the beta interferon drug which relieves the symptoms of some sufferers.
The Nationalist MSP said the committee would continue to push the executive.
Health Minister Malcolm Chisholm said he was recruiting more neurologists and increasing the use of the drug beta interferon.
And an executive spokesman said the minister would be meeting with representatives from the MS Society on Thursday.