(CNN) -- Ever since the dawn of photography, human beings have turned the camera on themselves, capturing the most expressive part of the human body -- the face.
Now, the art of photographic portraiture is taking center stage at a major international festival in Spain, showcasing the work of artists who have harnessed the power of the portrait in new ways.
PhotoEspana, offers 70 photography exhibitions in venues around Madrid until July 24. The theme of this year's festival is portraiture and communication, with the flagship show, "Face Contact" at Teatro Fernan Gomez, revealing the subversive, ironic and political potential of portraits through the work of 31 contemporary artists.
Among them is Mexican-born artist Dulce Pinzon, who dresses her subjects -- Mexican immigrants to the United States -- as super heroes. Each photograph is accompanied by text revealing the subject's heroic efforts, such as working long hours as a parcel delivery boy while managing to send home money to their family.
"It's very interesting because it shows Latin immigrants not as the usual representation of drug dealers or lazy people or criminals, but rather like hard workers who're doing jobs other people don't want to do. In a way they are super heroes," said exhibition and festival curator Gerardo Mosquera.
"Disguising them as these comic-book characters actually becomes a means to show their real characters," he added.
The stereotyping of immigrants is a theme also tackled by young Spanish artist Marta Soul, who captures recent arrivals to Madrid dressed up like models and posing in their brand new flats -- presenting them as successful people.
"I used the kind of dress that Spanish people wore back in the sixties when they left Spain to work in other European countries," Soul said. "I did not want to reproduce the prototypical journalist picture of immigrant people. I do not intend to show dramatic pictures. It is more about similarities than stressing social differences."
Like other artists in the exhibition, Soul does not see portraiture as an end in itself, but as a means of investigating contemporary issues.
"I see portraiture as a powerful tool to understand and express social values, roles, identity," she said. "I do not see myself necessarily as uniquely a portraiture artist. I like to represent scenes, irony, role-taking; and that involves making portraits."
Soul's approach echoes that of Colombian artist Libia Posada -- a doctor who takes photos of female patients from her hospital who have been victims of domestic violence. The dress and pose of the pictures references 17th century painted portraiture and makes the women look regal, despite their scars.
According to Mosquera, the enthusiasm of contemporary artists for the portrait is a sign of the times.
"We are living in an era of portraiture -- portraiture is all around us," he said. "All the time we are asked to show ID photos, there are surveillance cameras everywhere. It's very much about identifying you, keeping your image. Portraiture is all over the internet, it's the webcam, Facebook. So it's not surprising artists are also using portraiture a lot."
For Iranian artist Shadi Ghadirian, the festival's focus on portraits this year makes sense. "I think it's the right time to talk about portraiture, because of situations going on around the world," she said. "There are different countries with problems and many wars are happening because of religious or political factors. It means people are face to face with each other in new ways like never before.
"With portraits you have the facility to see other people in the world -- how they react, how they think, their ideas about different things," she added.
Ghadirian's work, included in Face Contact, questions the role of the armed forces in her home country with collages that combine old Iranian army photos with modern photojournalism.
Collage is also used to political effect by Jarbas Lopes, who weaves strips of photos of political candidates in Brazil to create a single, monstrous face.
Other artists prefer the self-portrait as a way of making a political statement.
Mumbai-based artist Shilpa Gupta appears in a series of photographs dressed in khaki, with multiple hands covering her ears, mouth and eyes, as a comment on the refusal of people to acknowledge the truth about the "unjust" war in Iraq.
"I often use not just one self but multiple selves in my photos," she said. "It's a way of being the 'other' yourself, of enacting other people's realities through yourself."
A previous video work of hers depicted seven Shilpas exercising simultaneously, but dressed in different clothes. "It emphasizes that I am Shilpa, I was born in Bombay and have these experiences, so I behave in a certain way -- but I could be the same person and be born in London and have a very different history," she said.
Fittingly, the Face Contact exhibition culminates with a portrait that will be familiar to every viewer. "We end with a work by the London-based artist Mona Hatoum, which is a small mirror," said Mosquera, "so after that long trip through portraiture you arrive at your own face."