how do i get enemy ai to avoid objects in scene

the enemy ai in my game will follow my just fine but when i go behind an object or when a take a turn inside of a building then the enemy will just collide with whatever i am behind instesd of going around it what can i do to my script to prevent this.--here is my ENEMY AI FOLLOW script--- #pragma strict

 var target : Transform; //the enemy's target
 var moveSpeed = 3; //move speed
 var rotationSpeed = 3; //speed of turning
 
 var myTransform : Transform; //current transform data of this enemy
 
 function Awake()
 {
     myTransform = transform; //cache transform data for easy access/preformance
 }
 
 function Start()
 {
      target = GameObject.FindWithTag("Player").transform; //target the player
 
 }
 
 function Update () {
     //rotate to look at the player
     myTransform.rotation = Quaternion.Slerp(myTransform.rotation,
     Quaternion.LookRotation(target.position - myTransform.position), rotationSpeed*Time.deltaTime);
 
     //move towards the player
     myTransform.position += myTransform.forward * moveSpeed * Time.deltaTime;
 
 
 }