The Scottish SPCA has appealed for support to extend its Glasgow Animal Rescue and Rehoming Centre, in Cardonald.
Known locally as the Glasgow Dog and Cat Home, the centre will be transformed over the next two years.
Scotland's animal welfare charity says the extended centre will be able to care for up to 3000 abused, abandoned and injured animals every year.
SSPCA Chief Superintendent Mike Flynn said: "Sadly, the extremely high number of animals coming into our care has been stretching our resources to their absolute limit, which is why this massive investment is vital.
"Our Glasgow centre is our largest and oldest. This is the most ambitious project we have ever undertaken."
The centre, which opened in 1908, cared for 1967 animals last year.
Once extended, it will house the only two- storey kennel blocks in Scotland.
Mr Flynn added: "We have limited space to build on and have developed an innovative solution.
"The three single-storey kennel blocks we have at the moment will be replaced with two-tiered kennel blocks, the first of their kind in the country. This will increase our kennel spaces from 99 to 150.
"With our cattery units increasing from 28 to 48 and new accommodation also being built for small animals and exotic pets, the centre will be able to care for up to 3000 abused, abandoned and injured animals every year.
"We are also investing significantly in our veterinary facilities, which will help our team perform routine and life-saving procedures and operations."
And the public are being asked to throw their support behind the charity's plans by helping raise funds.
Anyone wishing to donate to the Scottish SPCA's appeal can call 0800 160 1758 or visit www.scottishspca.org/glasgow
The Scottish SPCA is Scotland's animal welfare charity and in 2012, the charity's helpline received 195,299 calls.