"Then, use this captured value as the id for a new Contact object you construct - Not understood.

package com.teamtreehouse.contactmgr.controller;

import com.teamtreehouse.contactmgr.model.Contact;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.ui.ModelMap;

@Controller
public class ContactController {

    @RequestMapping("/")
    public String home() {
      return "index";
    }

    @RequestMapping("/contact/{id}")
    public String contact(@PathVariable int id,ModelMap modelMap) {
      Contact c = 

      modelMap.put("contact",c);
      return "contact_detail";
    }
}

package com.teamtreehouse.contactmgr.model;

public class Contact {
  private int id;
  private String firstName;
  private String lastName;
  private String email;

  public Contact() {}

  public Contact(int id, String firstName, String lastName, String email) {
    this.id = id;
    this.firstName = firstName;
    this.lastName = lastName;
    this.email = email;
  }

  public int getId() {
    return id;  
  }

  public String getFirstName() {
    return firstName;  
  }

  public String getLastName() {
    return lastName;  
  }

  public String getEmail() {
    return email;  
  }

  public void setId(int id) {
    this.id = id;  
  }

  public void setFirstName(String firstName) {
    this.firstName = firstName;  
  }

  public void setLastName(String lastName) {
    this.lastName = lastName;  
  }

  public void setEmail(String email) {
    this.email = email;
  }
}