Avoid the touristy tapas bars near Giralda. Poor service and greasy food and ice cold red wine.
Try the tapas where you see lots of the local people and you are sure of finding excellent food and wine.
Two we found were fantastic, one the other side of the Cathedral on Calle Santo Tomas near the Archivo de Indias. And the other called Cinco Jotas, Calle Castelar in the Arenal district.
Both serving delicious tapas, look and see what the locals are eating and drinking and point to the waiter, you can't go wrong.
Cinco Jotas, Calle Castelar 1, 41001, Sevilla
+34 954 210 763
www.mesoncincojotas.com/index_english.htm
Google map: tinyurl.com/y8zpl23
Updates
Some very good tapas bars next to the Giralda tower include Santo and Milagritos (in the Hotel EME), Cervecería Giralda (Mateos Gago 3), and for "cheap & cheerful" Bodega Santa Cruz (aka Las Columnas, Mateos Gago). Absolutely agree. I'm from Seville and Sintra is right. Azahar... if you go to Cervecería Giralda, be careful with the bill, they try to cheat even the locals!
Hundreds of bars only 300 metres away.
Is this your business?