A puppy that cries the entire night!  

awww..try putting leo in the bed with you.or somewere in your bedroom were he will feel secure.he may just be lonely.this may help him stop crying

Well did you call the vet? who knows he might be in pain that's why he cries all night. did you notice anything strange like maybe he walks funny or doesn't eat and drink regularly? I don't think a puppy will cry all night if nothing is wrong.

We had some neighbors who left their dogs outside and were away all weekend, every weekend. The dogs barked nearly non-stop so we purchased a Bark Silencer.

It is an electronic device (although you can run it on batteries also) that you turn on to record the offending dogs barks. Somehow, it translates these barks to a high frequency and plays it back every time the dog barks. It does not harm the dog; just annoys him. Within an hour or so, our neighbors dogs quit barking---for good. Once in a while we hear a little peep out of one of them as though he is testing the waters, so to speak, but our bark silencer gives it right back to him, and he stops immediately.

It was rather expensive -- $89 I believe, but it was worth every penny and has been borrowed by friends so it is really paying for itself. It can also be operated manually if you prefer, where, everytime you hear the dog bark, you push the button. It is much easier just to set it and forget it.

It will not stop a dog from barking at an intruder or for something serious, but he has to want to bark more than he wants not to hear that annoying noise coming back at him.
The human ear does not hear the noise at all. Our cat notices it, and is curious, but doesn't seem to be really bothered by it.

Good luck.

he's probabbly just not used to being alone. what i usually do is just keep him company, like let him sleep next to us at night, or just be visible. but if he still doesnt stop, we usually just leave him alone in a place that wont bother us that much until he just gets tired of crying.

Where do you want him to sleep when he is fully grown? If you start putting him in your bed now, that's where he'll be every night from now on! If you don't want him to sleep in your bed, you might try one of those toys they have for babies that have a heartbeat that he can here. Also, you might try putting a heated towel in bed with him for something warm to snuggle up with. He is only 1 month old? That's a little young to be weaned and away from his mother.

Actually, I read in a magazine that if you took a flashlight and shone it on his face every time he started to cry that he would stop. They apparently don't like having light in their face. It's supposed to break them of it pretty fast. Let me know if it works out for you.

Being only a month old he's a little bit young to be away from his brothers and sisters. However some things you can try are:
Put him in the laundry (or other enclosed area - where it's not too much of a problem for those overnight accidents) and leave a radio playing - he might just need to know he's not alone.
Let him sleep with a jumper or shirt that you've been wearing that has your scent on it.
Some suggest putting a clock in the room with them - the ticking reminds them of hearbeats.
With my shepherd it took her a few nights to really settle into a routine - we'd let her cry for a little while and then go in to let her know she wasn't alone, but wouldn't stay long and then leave.
If he sleeps on a blanket during the day, make sure you put that in with him of a night - you might try doing that putting that in your room on the floor by the bed so he learns that the blanket is his sleeping area - then slowly move the blanket to wherever it is you want him to spend the night.
Hope some of that helps - remember though the key to all dog training is patience and consistency :-)

one month = 4 weeks. he/she's too young to be away from mom. put him/her in bed with you. she/he needs a mommy. badly.

i think that he cries cause he's feel alone! try to take him with. however it could be that he feel cold or hot...it depends where is he! or it cuold be that he feel bad for some medical problems so u can take him to the veterinary

Your puppy misses his siblings and his mother! At a month old, he is really too young to leave them - usually they are not ready to leave the nest until they are 7-8 weeks old. He needs lots of love from you and you have to give him the security that he misses from his mother and siblings. Put a fluffy toy in his bed, warm blanket, and perhaps a clock placed under his blanket so he can hear the ticking sound to comfort him. He would probably like to curl up next to you in bed! Don't start that however, if you don't want to continue for the rest of his life. Hope this helps, and good luck.