Dr. Diehl has been the veterinarian for my dogs and cat for over a decade. He is by far the best vet I have ever used. His prices are reasonable, his care is exceptional, and his compassion limitless. The most difficult problem we ever faced was when one of my dogs had skin cancer. Dr. Diehl helped me understand the nature and expected course of the disease. He helped me chart the best treatment for my dog which kept her happy and healthy for the next two years. He surgically removed the lesions when possible and gently let me know when surgery would be ineffective due to the number of lesions present. In the end the cancer metastasized to her brain and she began to have grand mal seizures. When the inevitable end came, Dr. Diehl and his and his staff were extraordinary empathetic giving me and my dog as much comfort as humanly possible. The apple does not fall far from the tree for when my daughter's cat suffered acute renal failure, it was Dr. Diehl's daughter who's quick and decisive action saved my daughter's cat.

Dr. Diehl is the "worst" veterinarian in San Clemente. After taking my cat into his clinic to be evaluated he briefly "examined" her and without asking me any questions about her behavior/symptoms he quickly diagnosed her as simply being in heat. I was in and out of his office within two minutes. He charged me for the visit and recommended i get my cat spayed. Luckily, I took my cat to another clinic for the surgery and as it turned out, my cat was not in heat. In fact it was physically impossible for his diagnosis to be true since she had apparently already been spayed (i found my cat so there was no way i could have known this and I had made this information known to Dr. Diehl). My cat was misdiagnosed and recommended a unnecessary surgery. After this horrific ordeal, I made a visit to Dr. Diehl to inform him of his misdiagnosis and demand my money back for his examination which led to nothing but unnecessary pain for my poor cat. He was less than sympathetic, in fact, he showed me NO sympathy. He actually tried to blame his misdiagnosis on me!! He refused to refund my money, brought me to tears and didn't even offer my an apology! DO NOT TAKE YOUR PET TO THIS CLINIC! Giving this clinic even one star is too many!