A method for the assembly of a polynucleic acid sequence from a plurality of nucleic acid sequences in which the polynucleic acid sequence is of a formula N n+1, in which N represents a nucleic acid sequence and where n is 1 or greater than 1 and each N may be the same or a different nucleic acid sequence, in which the method comprises: (i) providing a first nucleic acid sequence N1 in a vector, using a restriction enzyme to cut the nucleic acid sequence out from the vector and ligating an oligonucleotide linker sequence L1 3' to the 3'-end of the nucleic acid sequence; (ii) providing a second nucleic acid sequence N2 in a vector, using a restriction enzyme to cut the nucleic acid sequence out from the vector and ligating an oligonucleotide linker sequence L2 5' to the 5'-end of the nucleic acid sequence, wherein the 5'-end linker sequence L2 5' of nucleic acid sequence N2 is complementary to the 3'-end linker sequence L1 3' of nucleic acid sequence N1; and ligating an oligonucleotide linker sequence L2 3' to the 3'-end of the nucleic acid sequence N2; (iii) providing one or more additional nucleic acid sequence(s) N in one or more vector(s), using a restriction enzyme to cut the nucleic acid sequence(s) out from the vector(s), wherein nucleic acid sequence N2 has an oligonucleotide linker sequence L2 3' at the 3'-end of the nucleic acid sequence, and wherein said one or more additional nucleic acid sequences N comprises a terminal additional nucleic acid sequence NZ, and ligating an oligonucleotide linker sequence to the 3'-end of each additional nucleic acid sequence N, wherein said terminal additional nucleic acid sequence NZ optionally lacks an oligonucleotide linker sequence at its 3'-end, and ligating an oligonucleotide linker sequence to the 5'-end of each additional nucleic acid sequence N, wherein for the first additional nucleic acid sequence N3 the 5'-end linker sequence L3 5' is complementary to the 3'-end linker sequence L2 3' of nucleic acid sequence N2 and for each second and subsequent additional nucleic acid sequence N the 5'-end linker sequence is complementary to the 3'-end linker sequence of the respective preceding additional nucleic acid sequence; and (iv) ligating said nucleic acid sequences to form said polynucleic acid sequence. (i) providing a first nucleic acid sequence N1 in a vector, using a restriction enzyme to cut the nucleic acid sequence out from the vector and ligating an oligonucleotide linker sequence L1 3' to the 3'-end of the nucleic acid sequence; (ii) providing a second nucleic acid sequence N2 in a vector, using a restriction enzyme to cut the nucleic acid sequence out from the vector and ligating an oligonucleotide linker sequence L2 5' to the 5'-end of the nucleic acid sequence, wherein the 5'-end linker sequence L2 5' of nucleic acid sequence N2 is complementary to the 3'-end linker sequence L1 3' of nucleic acid sequence N1; and ligating an oligonucleotide linker sequence L2 3' to the 3'-end of the nucleic acid sequence N2; (iii) providing one or more additional nucleic acid sequence(s) N in one or more vector(s), using a restriction enzyme to cut the nucleic acid sequence(s) out from the vector(s), wherein nucleic acid sequence N2 has an oligonucleotide linker sequence L2 3' at the 3'-end of the nucleic acid sequence, and wherein said one or more additional nucleic acid sequences N comprises a terminal additional nucleic acid sequence NZ, and ligating an oligonucleotide linker sequence to the 3'-end of each additional nucleic acid sequence N, wherein said terminal additional nucleic acid sequence NZ optionally lacks an oligonucleotide linker sequence at its 3'-end, and ligating an oligonucleotide linker sequence to the 5'-end of each additional nucleic acid sequence N, wherein for the first additional nucleic acid sequence N3 the 5'-end linker sequence L3 5' is complementary to the 3'-end linker sequence L2 3' of nucleic acid sequence N2 and for each second and subsequent additional nucleic acid sequence N the 5'-end linker sequence is complementary to the 3'-end linker sequence of the respective preceding additional nucleic acid sequence; and (iv) ligating said nucleic acid sequences to form said polynucleic acid sequence.