1.The beneficent deity Lalita Tripurasundari
2. Her mantra;
3.and the yantra known as Sri Chakra.
Srividya creates a systematic, esoteric discipline combining elements of the yogas of knowledge, of devotion, and of ritual.
In the Shakti form of worship, Srividyopasana (i.e., the pursuit of enlightenment via Srividya) is considered the pinnacle of achievement. If the aspirant is initiated properly, it is the ultimate path, because it gives you the experience of union with the Universe, the Cosmos - or whatever name you prefer to call IT by. It is said you must, in past lives, have done thousands of years of sadhana of all the devatas such as Vishnu, Shiva, etc. to reach this point. It is said that one can obtain initiation into Srividya only if one is in his/her or his final birth - or is verily Shiva Himself.
And within Srividyopasana there are stages of practice - from simple recitation of mantras to long and ritually complex mediations, all of which are followed progressively until suddenly you are THERE. In this context it is said that even if you are not really competent, some past meritorious karma can still you get initiated into Srividya, and you will become a yogabhrashta (an outcast in spiritual practice) – then in the next birth you will start where you stopped and will attain the union faster.