The Hairdresser and the Barber

There is a small difference in the way that Hair Salons and Barber Shops operate which perfectly illustrates a foundational principle of Service Design. Disclaimer: I’m no expert on the grooming industry as I like cheap, bad haircuts.

  • Hair Salons typically organise customer demand by taking bookings several weeks in advance. These bookings are recorded in a schedule and assigned to the customer’s preferred hairdresser. Walk-in customers are discouraged, and sometimes penalised by a higher price.
  • Barber Shops typically organise customer demand by using a first-come-first-served bench, or row of chairs. Customers arrive and are seated in a queue until one of the barbers becomes available.

Even though Hairdressers and Barbers trade in the exact same industry, these approaches have emerged to suit to the needs and preferences of their customers.

Let’s have a look at another, similar example.

The Vaccination Service

In this past week, the COVID-19 vaccination drive in South Africa has opened up for the 35-49 age-group. While older citizens have shown some hesitancy, there has been an enormous surge in demand from the younger group.

One of the biggest challenges for managers of vaccine sites, is how to organise and optimise the vaccination service to ensure that as many people get vaccinated, as quickly as possible. In other words, how to achieve maximum throughput.

From a Service Design perspective, two types of citizen behaviour have emerged:

  • Citizens that have registered online, and must wait for their vaccination appointment to be scheduled and confirmed.
  • Citizens that have walked in to vaccination centres, opportunistically hoping to fill someone else’s missed appointment.

Some customers have a flexible approach to personal productivity (“I make it up as I go”), whereas others prioritise rigid schedules filled with appointments (“My whole life is planned, don’t mess with my schedule!”). However these characteristics are still not useful in predicting whether a person prefers the certainty of scheduling or the flexibility of walk-in.

We should therefore consider designing a service offering to accommodate either preference. In this, you have the choice of designing your service to be Service-as-Available or Service-as-Scheduled.


Service-as-Available (SAA) provides the facility based on when the customer needs it. It is a seemingly chaotic approach, however it is also much easier to observe Queueing Theory in action. The queue on the bench is a visual indicator of the backlog. Prospective customers can make an informed decision to either take a seat and wait, or pop over to the supermarket for some groceries and come back later.

When to use Service-as-Available:

  • When the units of work (ie. haircut) are relatively short (ie. 20 minutes).
  • When there is no customer preference for a particular hair stylist.
  • When customers require flexibility.


Service-as-Scheduled (SAS) is the approach of mapping customer demand to a schedule, and ensuring Service Delivery matches that schedule. In the case of the Hair Salon, a customer makes a booking (phone-call, or online) and the booking is inserted into the calendar. At this point the booking may be assigned to a particular hair-stylist, or it may be allocated on a round-robin basis.

When to use the Service-as-Scheduled approach:

  • the units of work are relatively long (ie. 2-3 hours)
  • the customer has a preference for a particular stylist

There are, however, logistical issues with this approach. Should a hair-stylist unexpectedly fall ill, the rigidity of the schedule means that an inordinate amount of effort would need to go into renegotiating the schedule with affected customers.

The Hybrid Approach

The hybrid approach (both SAA and SAS) can also work, but it requires an understanding of how customer demand emerges, and a plan to manage it fairly. Employees involved in service delivery could easily become overwhelmed with aggrieved customers, especially those who booked weeks in advance who have observed walk-in customers jumping the queue.


While it may be tempting to offer only one type of service, over another, the flexibility of a carefully-considered hybrid approach will smooth over operational hiccups.