Budi daya udang di tambak tradisional telah menggunakan input komersial. Usaha ini belum menerapkan cara budi daya yang baik (CBIB), sehingga permasalahan produktivitas dan inefisiensi bepotensi terjadi. Dengan data hasil wawancara dari 182 petambak di Brebes, Lampung Selatan dan Indramayu (Mei - Agustus 2024), penelitian kuantitatif dengan metoda statistik deskriptif dan Stochastic Frontier Analysis ini bertujuan: menganalisis karakteristik, produktivitas, kinerja ekonomi, dan faktor inefisiensi budi daya udang menggunakan Software STATA 15. Temuan penting adalah: R/C rata-rata (2,7), tertinggi Brebes (3,1), Indramayu (2,5) dan Lampung Selatan (2,2). Monokultur udang menghasilkan pendapatan tertinggi (Rp57,17 juta/ha/siklus), polikultur bandeng (Rp56,56 juta/ha/siklus). Praktek penjarangan sekali, kolam tandon, pembuangan limbah teratur, dan sumber air dari sungai meningkatkan produktivitas. Namun, budi daya udang yang lokasinya jauh dari rumah dan jalan utama, mempunyai banyak petak efisiensinya rendah. Sebaliknya, semakin tinggi tingkat pendidikan, pengalaman petambak, modal yang memadai, luas tambak > 1 hektar, dan kepuasan petambak terhadap kelompok, meningkatkan efisiensi. Mengatur pemanfaatan petak tambak dalam berproduksi mampu mengatasi inefisiensi. Aksi kolektif bertujuan memperbaiki inefisiensi dan mendorong CBIB. Aksi ini dilakukan melalui pelatihan, pengadaan input, konsolidasi petak tambak untuk tandon air dan instalasi pembuangan limbah (IPAL). Federasi lintas wilayah dan tim teknis diperlukan untuk pencegahan penyakit udang. Korporasi untuk konsolidasi manajemen usaha perlu dibentuk agar tercapai skala ekonomi. Pemerintah diharapkan mendukung aksi kolektif ini agar pelatihan, dan CBIB dapat diwujudkan, sehingga budi daya udang menggunakan air yang berkualitas, dan budi daya itu bebas penyakit. Aksi kolektif peningkatan kapasitas petambak dapat mendorong perbaikan inßastruktur, membangun akses terhadap modal sehingga meningkatkan daya saing dan keberlanjutan usaha.TITLE: COLLECTIVE ACTION OF BRACKISHWATER FARMERS TO ENHANCE THE EFFICIENCY OF SHRIMP CULTIVATION IN TRADITIONAL BRACKISH WATER PONDSShrimp farming in traditional ponds has already utilized commercial inputs. However, this activity has not yet implemented good aquaculture practices (CBIB), which is likely to lead to productivity and eflciency issues. Using interview data from 182 shrimp farmers in Brebes, South Lampung, and Indramayu, this quantitative study, employing descriptive statistical methods and Stochastic Frontier Analysis, aims to analyze the characteristics, productivity, economic performance, and ineflciency factors of shrimp farming using Stata 15. Key findings are: R/C ratio averages 2.7, with the highest in Brebes (3.1), Indramayu (2.5), and South Lampung (2.2). Monoculture shrimp culture is the most income-generating (Rp57.17 million/ha/cycle), followed by milkfish polyculture (Rp56.56 million/ha/cycle). Productivity-enhancing technologies are single thinning, reservoir ponds, periodical waste removal, and river water use. However, shrimp farms located far from the farmer’s residence and main roads, and with many plots, tend to be less eflcient. On the other hand, higher levels of education, greater farming experience, suflcient capital, pond areas over 1 hectare, and farmer satisfaction with their groups improve eflciency. Managing the use of pond plots for production can overcome ineflciencies. Collective action aims to address ineflciency and promote CBIB. This action is implemented through training, procurement of inputs, consolidation of pond plots for water reservoirs, and the establishment of waste- disposal installations (IPALs). Cross-regional federations and technical teams are needed to prevent shrimp disease. Business management consolidation corporations should be formed to achieve economies of scale. The government needs to encourage this group action to achieve training and CBIB adoption, so that shrimp farmers can use quality water and remain disease-free. Collective capacity-building efforts among farmers can also promote infrastructure improvements, build access to capital, and thereby enhance competitiveness and business sustainability.