diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/BookingConfiguration.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/BookingConfiguration.java
new file mode 100644
index 0000000..3204622
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/BookingConfiguration.java
@@ -0,0 +1,18 @@
+package io.reflectoring.booking;
+
+import io.reflectoring.booking.business.BookingService;
+import org.springframework.context.annotation.Bean;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+import io.reflectoring.booking.data.BookingRepository;
+import io.reflectoring.customer.CustomerRepository;
+import io.reflectoring.flight.FlightRepository;
+
+@EnableJpaRepositories("re")
+public class BookingConfiguration {
+
+  @Bean
+  public BookingService bookingService(BookingRepository bookingRepository, CustomerRepository customerRepository, FlightRepository flightRepository) {
+    return new BookingService(bookingRepository, customerRepository, flightRepository);
+  }
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/BookingService.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/BookingService.java
new file mode 100644
index 0000000..b253a21
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/BookingService.java
@@ -0,0 +1,52 @@
+package io.reflectoring.booking.business;
+
+import java.util.Optional;
+
+import io.reflectoring.booking.data.Booking;
+import io.reflectoring.booking.data.BookingRepository;
+import io.reflectoring.customer.Customer;
+import io.reflectoring.customer.CustomerRepository;
+import io.reflectoring.flight.Flight;
+import io.reflectoring.flight.FlightRepository;
+
+public class BookingService {
+
+  private BookingRepository bookingRepository;
+
+  private CustomerRepository customerRepository;
+
+  private FlightRepository flightRepository;
+
+  public BookingService(
+          BookingRepository bookingRepository,
+          CustomerRepository customerRepository,
+          FlightRepository flightRepository) {
+    this.bookingRepository = bookingRepository;
+    this.customerRepository = customerRepository;
+    this.flightRepository = flightRepository;
+  }
+
+  /**
+   * Books the given flight for the given customer.
+   */
+  public Booking bookFlight(Long customerId, Long flightId) {
+
+    Optional<Customer> customer = customerRepository.findById(customerId);
+    if (!customer.isPresent()) {
+      throw new CustomerDoesNotExistException(customerId);
+    }
+
+    Optional<Flight> flight = flightRepository.findById(flightId);
+    if (!flight.isPresent()) {
+      throw new FlightDoesNotExistException(flightId);
+    }
+
+    Booking booking = Booking.builder()
+            .customer(customer.get())
+            .flight(flight.get())
+            .build();
+
+    return this.bookingRepository.save(booking);
+  }
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/CustomerDoesNotExistException.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/CustomerDoesNotExistException.java
new file mode 100644
index 0000000..6871018
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/CustomerDoesNotExistException.java
@@ -0,0 +1,9 @@
+package io.reflectoring.booking.business;
+
+class CustomerDoesNotExistException extends RuntimeException {
+
+  CustomerDoesNotExistException(Long customerId) {
+    super(String.format("A customer with ID '%d' doesn't exist!", customerId));
+  }
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/FlightDoesNotExistException.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/FlightDoesNotExistException.java
new file mode 100644
index 0000000..5119d20
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/business/FlightDoesNotExistException.java
@@ -0,0 +1,9 @@
+package io.reflectoring.booking.business;
+
+class FlightDoesNotExistException extends RuntimeException {
+
+  FlightDoesNotExistException(Long flightId) {
+    super(String.format("A flight with ID '%d' doesn't exist!", flightId));
+  }
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/data/Booking.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/data/Booking.java
new file mode 100644
index 0000000..3e47e74
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/data/Booking.java
@@ -0,0 +1,28 @@
+package io.reflectoring.booking.data;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+
+import io.reflectoring.customer.Customer;
+import io.reflectoring.flight.Flight;
+import lombok.Builder;
+import lombok.Data;
+
+@Entity
+@Data
+@Builder
+public class Booking {
+
+  @Id
+  @GeneratedValue
+  private Long id;
+
+  @ManyToOne
+  private Customer customer;
+
+  @ManyToOne
+  private Flight flight;
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/data/BookingRepository.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/data/BookingRepository.java
new file mode 100644
index 0000000..9c6ab25
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/data/BookingRepository.java
@@ -0,0 +1,6 @@
+package io.reflectoring.booking.data;
+
+import org.springframework.data.repository.CrudRepository;
+
+public interface BookingRepository extends CrudRepository<Booking, Long> {
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/web/BookingController.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/web/BookingController.java
new file mode 100644
index 0000000..4ef78b8
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/web/BookingController.java
@@ -0,0 +1,37 @@
+package io.reflectoring.booking.web;
+
+import io.reflectoring.booking.business.BookingService;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import io.reflectoring.booking.data.Booking;
+
+@RestController
+public class BookingController {
+
+  private BookingService bookingService;
+
+  public BookingController(BookingService bookingService) {
+    this.bookingService = bookingService;
+  }
+
+  @PostMapping("/booking")
+  public ResponseEntity<BookingResultResource> bookFlight(
+          @RequestParam("customerId") Long customerId,
+          @RequestParam("flightId") Long flightId) {
+    try {
+      Booking booking = bookingService.bookFlight(customerId, flightId);
+      BookingResultResource bookingResult = BookingResultResource.builder()
+              .success(true)
+              .build();
+      return ResponseEntity.ok(bookingResult);
+    } catch (Exception e) {
+      BookingResultResource bookingResult = BookingResultResource.builder()
+              .success(false)
+              .build();
+      return ResponseEntity.badRequest().body(bookingResult);
+    }
+  }
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/web/BookingResultResource.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/web/BookingResultResource.java
new file mode 100644
index 0000000..4a4c85f
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/booking/web/BookingResultResource.java
@@ -0,0 +1,12 @@
+package io.reflectoring.booking.web;
+
+import lombok.Builder;
+import lombok.Data;
+
+@Data
+@Builder
+public class BookingResultResource {
+
+  private boolean success;
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/customer/Customer.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/customer/Customer.java
new file mode 100644
index 0000000..df24d70
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/customer/Customer.java
@@ -0,0 +1,20 @@
+package io.reflectoring.customer;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+import lombok.Builder;
+import lombok.Data;
+
+@Entity
+@Data
+@Builder
+public class Customer {
+
+  @Id
+  @GeneratedValue
+  private Long id;
+
+  private String name;
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/customer/CustomerRepository.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/customer/CustomerRepository.java
new file mode 100644
index 0000000..4441bfb
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/customer/CustomerRepository.java
@@ -0,0 +1,6 @@
+package io.reflectoring.customer;
+
+import org.springframework.data.repository.CrudRepository;
+
+public interface CustomerRepository extends CrudRepository<Customer, Long> {
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/flight/Flight.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/flight/Flight.java
new file mode 100644
index 0000000..0b5dd6f
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/flight/Flight.java
@@ -0,0 +1,23 @@
+package io.reflectoring.flight;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+import lombok.Builder;
+import lombok.Data;
+
+@Entity
+@Data
+@Builder
+public class Flight {
+
+  @Id
+  @GeneratedValue
+  private Long id;
+
+  private String flightNumber;
+
+  private String airline;
+
+}
diff --git a/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/flight/FlightRepository.java b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/flight/FlightRepository.java
new file mode 100644
index 0000000..3b09c83
--- /dev/null
+++ b/spring-boot/spring-boot-testing/src/main/java/io/reflectoring/flight/FlightRepository.java
@@ -0,0 +1,6 @@
+package io.reflectoring.flight;
+
+import org.springframework.data.repository.CrudRepository;
+
+public interface FlightRepository extends CrudRepository<Flight, Long> {
+}