“This is probably the most popular subject we are dealing with this year,” said Mr. Barthassat, who has introduced a bill that would ban the import, export and domestic commercial trade in cat fur. “By this summer, it will be resolved. It is very personal for many people because cats are more than animals to us.”

Regardless of how common it is, news media reports over the past year across Europe portraying Switzerland as a cat-slaying haven have helped S O S Chats press its case. “The politicians must be careful what they say, but that they are helping us is a good thing,” said Tomi Tomek, the director of S O S Chats, who has lived since 1981 at a 260-cat shelter nestled in the rugged western Swiss mountains near Neuchâtel. “All of this publicity has driven the trade underground, and that is good, too.”

The matter would most likely have reached the Swiss Parliament in some form this year regardless of the activism and publicity because the European Union has required member states to prohibit the import and export of cat fur by the end of 2008 anyway. Switzerland is not a member of the Union but does have treaties that require it to adhere to many of its rules on trade matters. Mr. Barthassat’s effort to end the domestic trade, however, is a step beyond the European Union’s demands.

Ms. Tomek said her organization had spent a decade trying to bring attention to the use of cat fur and the theft of domestic cats. She said one of the biggest problems her group faced was to convince people that there really was a trade in cat fur.

“For a long time, nobody believed us because we had no proof,” she said. “We would call up the tanners and tell them who we were and ask them, and they would never admit they did this. Then we started just pretending we wanted to order some cat fur, and they sold to us. Now we are not seen as liars anymore.”

Armed with a thicket of receipts showing purchases by S O S Chats of cat fur garments as recently as last August, Ms. Tomek approached journalists from across Europe, persuading several to look into the matter.

Until she saw the news reports, Mrs. Nydegger herself dismissed Mrs. Tomek and others as radicals. But the loss of her third cat, Merlin, was particularly shocking because he was so loyal and well behaved, often taking walks with her and her dogs without a leash. That Merlin would have wandered off, she said, is “just completely impossible.”