Kasinadhuni Viswanath or K. Viswanath (Telugu: కాశినాథుని విశ్వనాథ్, is an acclaimed Telugu film director and actor whose contributions have been significant to Indian films through the Telugu film industry.
Viswanath was born to Sri Kasinadhuni Subrahmanyam and Sri Kasinadhuni Saraswatamma. He hails from Peddapulivarru, near Tenali in Andhra Pradesh. His hometown is Vijayawada.
Viswanath began his career as a technician in a studio at Chennai and later assisted Mr. Adurti Subba Rao in direction.He also worked as an assistant to director Ramnoth. He also wished to work as an assistant to K. Balachander and Bapu.  He debuted as a director with Aatma Gowravam, which starred Akkineni Nageswara Rao. However, his full prowess in film-making flowered with a subsequent film called Siri Siri Muvva.
His films used to tackle the relevance and influence of Indian music/culture/art in the modern era. Films in this mould include Sankarabharanam ('Lord Shankara (shiva)'s Ornament'). He made a series of such classical oriented movies all showcasing the bliss in Indian art forms. The list includes Saagara Sangamam ('A Tryst With Infinity'), Sruthi Layalu, Sirivennela ('Golden Moonlight'), Swarnakamalam ('Golden Lotus'), and Swathi Kiranam ('A Ray of Talent').
Vishwanath also made significant contributions on the social front with films like Saptapadi ('The seven Steps', signifying the sanctity of the Hindu marriage system), Swathi Muthyam ('Pure Pearl'), Swayam Krushi ("Attitude Towards Work" — conveying the message that dilligence and dedication is indispensable in achieving success), Subhodayam ('Good Morning'), Subhalekha ('Wedding Invitation' — a critique of the dowry system), Aapadhbhaandhavudu ('Savior'), and Subha Sankalpam ('Good Will').
Swathi Muthyam was India's official entry to the Oscars in 1986. Viswanath was awarded the Padma Shri by the Government of India for his contributions to Indian film.
His films mirror the erosion of cherished values of Indian culture yet he remains critical of those morals that make one stand against his fellow human. For example, in his movie Saptapadi, Vishwanath brilliantly addresses certain loopholes in an inadmissible cultural system like intercaste marriage. A temple chief-priest gets his daughter’s daughter married to his son’s son – unaware that she is musically fused to a flutist who is a Dalit (one of a lower caste, but of a higher humanness.) Later, as the priest sees the marriage falling apart, he comes to know the heroine’s erstwhile bonding. It takes the priest intense introspection to realise how nasty it is to look down upon a fellow human because of getting imprisoned in caste. He could now anchor his judgment of someone in the “content of character” rather than caste. Across numerous other films, Vishwanath has reechoed similar social concerns that still resonate in the audiences’ minds.
The music for his films was composed by K. V. Mahadevan and Ilaiyaraaja. Viswanath has also worked with artists like Hariprasad Chaurasia, Kelucharan Mohapatra and Sharon Loven for some of his films.
Viswanath also ventured into mainstream acting recently in Tamil like Kuruthi Punal(stg*Kamal Haasan,Arjun),Kakkai Chiraginile(stg*Parthiban),Mugavari(stg*Ajith),Bhagavathy(stg*Vijay),Pudiya Geethai(stg*Vijay) and Yaradi Nee Mohini(stg*Dhanush),Pandurangadu(stg*Balakrishna,Sneha),Tagore(Stg*Chiranjeevi),Aadavari Maatalaku Ardhaale Verule(stg*Venkatesh,Trisha Krishnan),etc.Mr Viswanath is currently playing the lead in SIVA NARAYANA TEERTHAM in TTD's Sri Venkateswara Bhakthi Channel(SVBC).
Mr.Viswanath is married to Jayalakshmi. The couple have three children,Padmavathi Devi,Nagendranath (alumnus of Andhra University,Vishakapatnam),Ravinadranath (alumnus of XLRI Jamshedpur and BITS Pilani)
* Father - Sri Kasinadhuni Subrahmanyam
* Mother - Sri Kasinadhuni Saraswatamma
* Spouse - Kasinadhuni Jayalakshmi
* Daughter - Kasinadhuni Padmavathi Devi
* Son(s) - Kasinadhuni Nagendranath,Kasinadhuni Ravindranath
* Son In Law - Vadrevu Pramod Kumar
* Daughter In Law(s) -Kasinadhuni Durgavara Lakshmi, Kasinadhuni Gouri Mohini
* Grandson(s) - Naren,Pranav
* Grand Daughter(s) - Hema,Swarna,Sivani,Krishna Gayatri
The Kasinadhuni's belong to the Lingadhari clan. The Kasinadhunis's are also related to the Sripathi Panditarajhulas family, a prominent family member being S P Balasubrahmanyam. Mr.Viswanath and Mr.Balasubrahmanyam are relatives. The Kasinadhunis's enjoy spending time together as a family. Mr.Viswanath loves spending time with his grand children.
* Most of Mr.Viswanaths's films have titles beginning with the letter "S"
* Mr.Viswanath introduced song writer, Sirivennela Seetaramasatry through the film Sirivennela.
* Mr.Viswanath also introduced song writerSri Veturi Sundara Ramamurthy
* Producer Edida Nageswara Rao considers Mr.Viswanath as his godfather since Mr.Viswanath was highly responsible for the success of Mr.Raos's production company, Poornodaya Arts. Poornodaya Arts gave in some fantastic hits by Mr.Viswanath, not to mention Shankarabharanam and Sagara Sangamam which are considered to be masterpieces to date.
* Kalavaramaye Madilo a 2009 movie starring Kamal Kamaraju and Swati Reddy, often referred to as Colors Swathi was appreciated by Mr.Viswanath. Director Satish Kasetty said that he was really blessed and fortunate to receive appreciations and blessings by his godfather, guru Mr.Viswanath.
* Chiranjeevi, the Megastar of Tollywood considers Mr.Viswanath his guru. He said at the 30 years celebration of Poornodaya Atrs function that " I learnt acting from my gurugaru, Viswanath garu. He told me how to act and he brought out the actor in me." Chiranjeevi was considered a mass hero by fansn. He acted a completely different role of Sambayya in Swayamkrushi, for which he gained recognition as a "true actor"
* Rakesh Roshan, father of Hrithik Roshan, after the success of 'koi mil gaya' said "i can say my son is a good actor if K.Viswanath makes a film with him".