Shelter in the spiritual sense suggests sanctuary a space wherein we will not be harmed but can be ourselves. The other image of shelter is protectiveness that is, actively participating in giving shelter or sanctuary. If we are giving shelter to someone in dreams, we may be protecting a part of ourselves from hurt or difficulty. If we are being given shelter we are aware that there is protective power in our lives. Any shelter signifies protection. We are all aware of the need for a safe space, and this symbolism comes across in dreams quite strongly. The images used could be anything from a snail shell to an umbrella. Usually dreams about shelter highlight our needs or insecurities. You might also like to consult the entries for Shells and Umbrella.