"I have been running Butlerforyou.com since 2008 and since then, each year I introduce more female candidates through word by mouth referrals and recommendations," he said, noting that the increase in demand was being driven by soaring standards of living among the world's new super- rich – both male and female.
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While high-net-worth women felt more comfortable with a female running their households, likewise, male employers in the Middle East preferred a female head of staff for cultural reasons, he noted.
"The scale of the properties and palaces is not understood by most people. I often have 40 people that work for me at one or more properties," Marcia Long, a female butler and estate manager originally from Chicago who has worked in the profession for 25 years, told CNBC.
"My work as a butler and estate manager is to ensure the highest standards of service throughout the estates. Basically, [that means] ensuring that everything is running smoothly so that my employer doesn't need to think about a thing regarding the property. It also means being proactive and anticipatory," she noted.
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Indeed, while an early 20th century butler like Carson of "Downton Abbey" might have been solely in charge of the wine cellar and dispensing liquors (the word "butler" comes from the old French term "botellier" or "bottle bearer"), the modern butler like Long is more akin to a personal assistant, organising every part of their employer's life as well as the home, domestic staff and guests.
"It is not uncommon for me to receive royals and dignitaries on a daily basis [or] for me to be asked to bid on artwork at an auction house or oversee renovations on a property. I leave in the evening when my client is settled and doesn't require more service," Long noted.
The annual salary for a butler can range between 50,000 to 150,000 euros ($69,000 - $205,000), according to Robert Wennekes, head of "The International Butler Academy" (TIBA) in the Netherlands, but the money does not come without a price. "If you're in it for the money then you're in the wrong profession," he told CNBC.
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His academy puts trainees through their paces over an eight-week course and expects students to put in up to 18 hours of work a day, replicating the real-life experience of a butler. Butlers don't always work in the traditional country house, with Middle Eastern palaces just as likely to be the place of work as a country estate. Hirsch's butler agency was in the process of recruiting for a female butler and "interior manager" for a super yacht in Monaco, for example.
The course attracts about 45 students each year who train at the academy's headquarters in the Netherlands but the school also runs corporate training courses abroad, attracting a further 200 students a year. The eight-week course at the academy and the expertise gained there comes at a price: 13,750 euros ($18,870).
Ninety-five percent of the students who follow the entire course until the end will graduate with a diploma, the butler academy told CNBC. However, those who do not stick to the academy's strict code of conduct could be asked to leave, the academy's director of recruitment, Frank Fortgens, told CNBC.
"Almost every course we have one or more students who cannot handle the pressure or do not accept the intensive discipline. Most of them decide to step back or we ask them to leave if the act against the pledge," he said.
Around one in four of the students in the Dutch academy are women, academy head Wennekes added, noting that their subsequent chances of gaining employment were down to the personal preferences of employers looking for a head of staff.
"Some employers will appreciate a female butler more than a male one simply due to cultural differences – for instance, in Saudi Arabia a male employer would be reluctant to leave the house with a male butler in charge. Other employers even specify whether they want an attractive or ugly butler."
As odd as that sounds, Wennekes said, employers require someone they can work with extremely closely for many hours a day and, as such, often had very specific requirements. Despite such proximity and reliance, however, he noted he had only ever seen one case of sexual harassment during his experience of running the academy's accompanying staffing agency.