New chihuahuas will have no idea where the bathroom is unless you make it very clear to her (or him), so the first thing you should do with a new chihuahua is spend time with them and let them know where things are...the place to sleep, the toys, and the bathroom.

Chihuahuas by nature will just go when they have to, and are rather carefree about it at first, so you will need to spend time around her, and help her to know the rules and procedures.

If your chihuahua has been with you for a while, and she (or he) is still making mistakes, then you should first know that these loving dogs respond best to positive reinforcement. This means you should spend most of your time on commending good behavior rather than discliplining your chihuahua when mistakes are made.

If you want to correct any problems with peeing or pooing in the house, confine your chihuahua to a small room when he sleeps at night, since they dislike using their sleeping area for a toilet. First thing in the morning, take your dog out to where you want her "area" to be, and keep her there until the business is done. Then commend her, and be very affectionate, and use a soft voice. This bonds the chihuahua with you, and creates a desire to repeat the experience.

If you have been active in disciplining your chihuahua and are feeling frustration, you might want to know that chihuahuas are pain avoiders, so she might be running off and doing the business in a secret spot, and disappearing before you discipline her. Again, positive reinforcement is the key to getting your chihuahua house trained and happy.

If punishment is used, it should only be given when catching her in the act, or within a few seconds of the bad behavior, otherwise the dog won't know why you are angry. Punishment should only be a stern voice and facial expressions, since chihuahuas are very perceptive. Beating your dog is not a good idea, since it will create avoidance behaviors (example: do not poo on the living room carpet), rather than focused good behaviors (poo in the garden near the fence).

Male chihuahuas have "marking" built into their brain, and you will not change them. Basically, they can pee on demand. You can teach your male to go to a particular spot when he wants to mark. One woman had a house-bound male, and succeeded in paper training him by laying plastic down, then paper, then put a full bottle on top that was covered in dog urine. She then worked with her male dog to give him praise when he urinated on the bottle.

Other more methods of house training include crate training and outdoor training, so you might want to investigate these methods if you are not having success within 4 weeks.

If you are at your wits end after using everything mentioned here, you should get advanced help, because sometimes professional advice is the only thing that can bring success in house training your chihuahua.

Chihuahuas are smart, loving dogs, and a joy to have when they learn the rules and respect you, so be kind and firm, and enjoy your time with your little buddy.